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Tuning The 2.25


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Just a warning to Series owners based on a recent learning. Over Christmas while in the UK I bough a set of the bolt on round circle strap type diff guards from Simmonites (front and rear). Very solid hefty bits and I guess they're elctroplated or something to stop rust. Bought them on the premises and specified that they were for a Series III SWB.<P>Put them on this week. Big problem on front diff. The guard bolts on with a tightening collar at the top and part of the guard comes about halfway up the front face of the diff with a sort of swoop/v and a bulge/lip along the top. Went on fine. However.... [image]images/icons/mad.gif" border="0"> <P>Once on, this bulge/lip was fouling the trac rod making steering a no-go. I had to have the face cut back down to below the level of the track rod and the "lip" removed so as not to foul the track rod but it's still pretty tight and I will have to keep checking to see that there is no rubbing during off road flexing. In any event, it's buggered the electro-plating so it will probably rust... <IMG SRC="images/icons/mad.gif" border="0[/image] <P>I've bought some other bits from Simmonites and they've been nice and helpful and by all accounts have a good reputation. When I called to explain the problem, I did not get joy. I wondered if maybe I had been given a different diff guard for a Defender rather than a Series model, "I don't know if they are different". Fair enough. Well it was a pain and and expense to have it cut back."Well it's alright now you've fixed it, right". Not very impressive as a response. Anyway, Series owners beware...<P>On to new gadgets.Just put a tachometer and an oil temp gauge into the Tonka:<P>The Tachometer wobbles a fair bit (rather like my speedo) particularly during acceleration. It can wobble about 800 rpm on the dial during acceleration. Is this an acceptable/normal tolerance ? If not, what is the likely culprit/how to fix ? BTW it's a brand new VDO gauge, so it shouldn't be carp...<P>Now that the tacho is in, I have a question on safe rev levels. With the ACR PowerPlus kit, the engine should produce max torque at @ 3400 rpm. Am I correct in assuming that I should view @ 3600 rpm as the red line safety buffer, or have I got much more room than that ? What are the generally recognised safe operating limits for a 23 year old 2.25 petrol ?<P>Finally, and this is me being lazy because I haven't checked the oil specs, can anyone tell me what the upper end oil temp should be (Farenheit, please) for Mobile 1 Synthetic oil 15w 50 ?<P>Cheers,

Post Extras:

fisha

(Member)

01/03/02 10:37 PM

Re: Warning For Series Owners & New Gadget Questions Reply

how is your tacho connected?

I assume its electronic and taking its pulses off one of the dizzy lines?

The likely reason it would vary is that its being fed a varying signal or that you are losing some of the pulse signals somwhere along the line.

All connections OK and solid?

Is the guage well grounded/earthed?

I wired my VDO guage directly into the W terminal of the alternator. ( i have a diesel Tdi ) and it has never or vibrated its reading.

[ 01-03-2002: Message edited by: fisha ]

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Ezzie

(Member)

01/03/02 11:08 PM

Re: Warning For Series Owners & New Gadget Questions Reply

I think that these engines have a specified max rev limit of 4600. Though going over 4000 for anything short of a few seconds is probably not a good idea. My tachometer has the occasional misbeat but in no way does it wander like yours does. If its something to do with the ignition and not a bad connection it'll show up on a vacuum guage as well, they're cheap, easy to fit and very useful. Check out this link: Series Shed Vacuum guage fitting

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RPR

(Member)

01/04/02 12:01 AM

Re: Warning For Series Owners & New Gadget Questions Reply

quote:

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Originally posted by fisha:

how is your tacho connected?

I assume its electronic and taking its pulses off one of the dizzy lines?

All connections OK and solid?

Is the guage well grounded/earthed?

I wired my VDO guage directly into the W terminal of the alternator. ( i have a diesel Tdi ) and it has never or vibrated its reading.

[ 01-03-2002: Message edited by: fisha ]

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All connections look good and mine is wired into alternator as well. On driving home this evening, I noticed that the big wobble is really only in fourth at higher speeds, so I think it may be settling in a bit. I'll give it a week, and then if it's still wobbling, I may dis and re connect...

Cheers,

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RolandM

(Member)

01/04/02 12:01 AM

Re: Warning For Series Owners & New Gadget Questions Reply

We set the Power Plus engine red line at 5200RPM this will give plenty of safety margin as they will run to 5700 on an intermittent basis with no problems. There is little to be gained by running much over 4800 as the power falls off rapidly over this point. However if you enjoy using the power e.g. racing rush hour traffic, off road competition etc it is useful to be able to run past maximum power so that the engine drops into a more favourable part of the power band on changing up a gear as the spacing between gear ratios on the 4 speed box is large. Regarding oil temperature the red line is around 250 however Mobil 1 will work safely well beyond that . We would keep the 250 as the upper maximum it is very unlikely even desert temperatures will push the temperature this high.

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R Turner

(Member)

01/04/02 03:57 AM

Re: Warning For Series Owners & New Gadget Questions Reply

Personally I cannot abide engines that have to be revved to perform and prefer to tune for low speed torque.

It is interesting how people always get exited by great bhp claims that can only be produced under controlled conditions and never mention torque output. Not realising that the higher bhp figures can only be achieved at very high rpm and would not be comfortable driving under these circumstances. High bhp will not normally be found at low speed making the torque output of the engine far more relevant. Torque is a reading taken at much lower rpm (approx 2750), whereas bhp being a product of multiplication increases the higher the engine is revved.

If anyone has stood next to an engine running on a dynomometer at 4000 rpm pulling maximum bhp, after a few seconds you feel like wanting to take two steps backwards. Visitors to our factory watching this type of test never looked particularly comfortable observing this type of test. Most stated that they did not realise this was how maximum bhp was measured.

Mechanical and thermal loads rise rapidly the higher the rpm. The increase in loading is not linear. Engines used under race conditions are usually rebuilt after only a few hours use and can very often show wear consistent with high rpm and high loadings.

The 2.25 Land Rover engines have heavy rotating and reciprocating components and most are not built with bearings suitable for race conditions. Fortunately 2.25 petrol engines are a relatively cheap commodity and therefore do not represent a major financial risk to most people. A major failure in a lot of cases can be regarded as fun by the mechanically competent or those prepared to wreck cheap used engines, but a major set back for those who have to pay others to fix their disasters.

Heavy vehicles benefit from more torque low down the rev range, not high bhp. I have had various dealings with people in the racing industry over the years, most would trade high bhp for midspeed grunt and driveability.

Richard Turner

www.turner-engineering.co.uk

[ 01-03-2002: Message edited by: R Turner ]

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Noel Clark

(Member)

01/04/02 09:14 AM

Re: Warning For Series Owners & New Gadget Questions Reply

RPR, the max rev limit I can see in Land Rover's official documentation is 4,250rpm.

RolandACR, no matter how hard you try you'll never get a Land Rover to be a Fiesta XR2 which seems to be what your conversions are all about.

R Turner, couldn't agree more.

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fisha

(Member)

01/04/02 04:33 PM

Re: Warning For Series Owners & New Gadget Questions Reply

RPR,

if its running from the alt, could it be something as simple as the belt slipping on the alternator pulley, each time it slips, the alternator will change speed and give the pulsing?

would be probably be most noticable under acceleration / deceleration.

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ChrisW

(Member)

01/04/02 05:58 PM

Re: Warning For Series Owners & New Gadget Questions Reply

How much is a tacho? Couuld one be acquired from a breakers yard and it work properly?

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rtbarton

(Member)

01/04/02 06:40 PM

Re: Warning For Series Owners & New Gadget Questions Reply

If you get one from a breakers yard bear in mind if it is connected to the distributor that you need to get one off a car with the same number of cyclinders as yours and that not all tachos are compatible with electronic ignition systems.

If you get an alternator driven one the ratio between the crankshaft and alternator pullies must be the same for both vehicles.

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Pete Johnson

(Member)

01/04/02 11:34 PM

Re: Warning For Series Owners & New Gadget Questions Reply

I ve bought from Simmonites once before.. Id rather set fire to my landy of leave it to rot than buy from them again.

I got a quote for tyres from them (was passing and needed them as two were stuffed) included free fitting and balancing. They phoned back to confirm they had stock and the price. So called in. They trashed the 3 good tyres getting them off despite me saying i wanted em... Only balanced the front pair and tried to charge me £60 on the tyre price and balancing and fitting!!!

Driving on to manchester very bad vibration from the front... Called into ATS got the lot rebalanced. the fronts needed a lot of lead and no where near it had been put by simonites.

going back 7 years to a Billing... They had a brand new series delux dished bonnet £80. A friend went to buy it... they said that was the exchange price!!! as the new bonnet didn't have hinges or the holes drilled for em he walked away. The bonnet was still for sale last year for £60!!!!

Ho Hum

Pete

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RolandM

(Member)

01/07/02 07:49 PM

Re: Warning For Series Owners & New Gadget Questions Reply

In reply to Richard Turners comments. The whole purpose of our Power Plus modifications is to produce torque! Here are the facts. On our latest 2.8 engine upgrade 120Ib.ft @ 980RPM (this is more than the standard 2.25 produces at its peak) 177Ib.ft @ 2300RPM. 117BHP @4100RPM as you can see these figures speak for themselves, more torque at 1000RPM lower down than 3.5V8!

Regarding the 2.25 to produce power it is wrong to state that this engine will become unreliable if fitted with our Power Plus modifications. In fact some of our early installatins have completed over 100,000 miles. Our modifications have an excellent reliability record confirmed by customer testimonials and product surveys. Our products are carefully designed and tested prior to release lets face it off road and on the 2.25 in standard form ia an under powered slug especially in heavy vehicles such as 109 station wagon where in modern traffic they are quite unsuitable. It is in these situations that the Power Plus system excels. By the way I never did like the Fiesta XR2, are there any still left out there?

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R Turner

(Member)

01/08/02 12:41 AM

Re: Warning For Series Owners & New Gadget Questions Reply

Roland

Where did anybody discuss a 2.8 hybrid engine?

The purpose of the discussion was to debate the reliability issues concerning normal day to day used engines having covered relatively high mileages from new and which are used for normal motoring in order that LR owners can better understand the implications of modifying their existing engine.

The comments concerning claimed performance output of some non standard 2.8 modified engine are completely irrelevant to the argument.

Any modification that affects power output or fundamentally interferes with mixtures or compression ratio outside of the original manufacturers intentions will affect reliablility and life expectancy. I have discussed this issue at length over the years with component manufacturers and independent engineers concerned with examination of failed engines of all makes and types and indeed people in the performance industy. This is fact.

Unfortunately none of the Land Rover magazines have sofar chosen to conduct independent trials of aftermarket products to verify whether the claims made are true or otherwise. This does little to assist the buying public as to what represents value for money.

Richard Turner

www.turner-engineering.co.uk

[ 01-07-2002: Message edited by: R Turner ]

[ 01-07-2002: Message edited by: R Turner ]

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RolandM

(Member)

01/08/02 11:00 PM

Re: Warning For Series Owners & New Gadget Questions Reply

Richard It is wrong to say that independant tests and magazine articles ahve not been conducted. Please refer to LRO Carl Rogerson Oct'97, LRW Matt Ross June'99 & Steve Anderson Nov'00, LRM Mike Yardley Apr'99. These articles are independant proof that our modifications are all about torque and driveability. Everyone must surely agree that Series vehicles need more power and that it is preferable to improve the original than fit some unsuitable conversion. Thankfully the 2.25 is so understressed the safety margins from the reliability point of view are enormous, even in tuned form infact used as a supercharged race engine, as we do for use in international rallying and off road racing - Yes it is competative against ex. worl rally Subaru Imprezza and Mitsubishi Evo. The standard 2.25 components within that engine withstand the very heavy loadings reliability and without strip down or rebuild from one season to the next.

It seems to me that you simply cannot accept that our product is successful and use occasions such as this simply to attack ACR. One thing I do agree though is that a controlled trial of ACR Power Plus engines against conversions and other aftermarket products would indeed make a very interesting magazine article.

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gruntie

(Member)

01/08/02 11:34 PM

Re: Warning For Series Owners & New Gadget Questions Reply

quote:

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The Tachometer wobbles a fair bit (rather like my speedo) particularly during acceleration. It can wobble about 800 rpm on the dial during acceleration. Is this an acceptable/normal tolerance ? If not, what is the likely culprit/how to fix ? BTW it's a brand new VDO gauge, so it shouldn't be carp...

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Check the points. The tach starts to bounce when the points are starting to wear and the gap closes up.

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R Turner

(Member)

01/09/02 02:28 AM

Re: Warning For Series Owners & New Gadget Questions Reply

Roland

I am not attacking your product. I merely re-iterate that the purpose of the debate is to establish whether it is sensible to rev a 30 yr old engine in excess of 5000rpm, which you state is safe and will not cause shortening of the life expectancy.

Keep in mind that the life expectancy of a new 2.25 petrol engine is in the region of 3 to 400.000 miles. The question is - will a 2.25 petrol still achieve 3 to 400.000 miles if revved to in excess of 5000rpm on a regular basis or if it has allready covered many miles. At this point it would be useful to mention our experience of examining failed military engines. These engines are normally unsympathetically driven and suffer failures not normally seen in civilian used engines. It is not uncommon to see broken pistons, loose small end bushes and other types of damage consistent with high speed operation. The statement that an engine can be safely revved to in excess of 5000 revs on a regular basis without risk is untrue.

Road tests carried out be magazines are not independent proof or verification of a suppliers claims and we would include ourselves as far as this is concerned.Many articles have been written over the years about Turner Engineering.

The only tests that are truly valid on performance related products would be tests carried out by an independent test house using calibrated and computerised equipment, comprehensive gas analysis equipment and carried out by independent unbiased engineers who do not receive payment for advertising.

We as a company have deliberately avoided non standard performance products due to the high cost of employing independent consultants to develop products for which there is a limited market. To go it alone as you have done is a brave move and I admire you for that. If what you claim is true, you have a succesful product.

If however judging by the debates from various websites around the world concerning speculation about our own products and what our gasflowed head will or will not do. Bearing in mind we make no specific claims to avoid unqualified speculation. If this speculation is anything to go by, the buying public are very cynical. Probably more cynical than I am. Roland, good luck, I hope you have got your sums right because the buying public will bite you on the bum if you haven't

I think it would be productive at this stage to agree to differ. Turner Engineering operate in a different area of the market than ACR as the overwhelming majority of our work is service exchange engines. Unfortunately I no longer have the time to play, and I have blown up a few engines in years gone by by playing around.

Richard Turner

www.turner-engineering.co.uk

[ 01-08-2002: Message edited by: R Turner ]

Post Extras:

Bigfoot

(Member)

01/09/02 03:40 AM

Re: Warning For Series Owners & New Gadget Questions Reply

Richard - I've been reading your posts on various threads with great interest. I finally clicked on the link to your website and I've found it very impressive and informative.

With reference to the 300 Tdi, am I correct in concluding that your recommendation for improvement in torque would be a gas flowed cylinder head? What is your opinion on big intercoolers and increased fueling?

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David Humphrey

(Member)

01/09/02 04:24 AM

Re: Warning For Series Owners & New Gadget Questions Reply

RPR.

I also bought a front diff guard at billing a couple of years ago - not from Simmonites I must add. This also needed to be cut to avoid fouling the track rod. Where you have cut, treat the 'wound' with cold galvanising paint - Galvafroid - available from Halfords etc. A local garage would probably have a tin to hand and if asked nicely may paint the cut for you to save buying a tin as it is quite expensive.

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Noel Clark

(Member)

01/09/02 06:03 AM

Re: Warning For Series Owners & New Gadget Questions Reply

quote:

--------------------------------------------------------------------------------

Originally posted by RolandACR:

Everyone must surely agree that Series vehicles need more power...

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Nope. Everyone most certainly does not. Speaking as someone who is driving 20+ year old buses about to make a few quid at the moment I can testify that a 2.25 Land Rover does not need more power - the driver needs to be more aware and observant and understand the limitations of the vehicle. The aforementioned buses have a kerbweight a shade under 10 tonnes and have 10.45 litre 6 cylinder non-turbo diesel engines that develop 170bhp. I have no problems with their performance (either acceleration or braking) in heavy traffic, dual carriageway work, country roads etc and they are infinitely slower than a 2.25 Land Rover.

It all comes down to vehicle sympathy, at the end of the day if you want a Land Rover to compete with Trevor in his GTI then a 2.25 litre motor isn't the one for you. Come to think of it, a Land Rover probably isn't for you unless it's a JE Engineering supercharged Range Rover or something like that.

You cannot change the laws of physics and no matter what you say, a 2.25 litre Land Rover engine, mucked about with to generate more power and revved beyond 5000 rpm on a regular basis cannot possibly last as long as an unmodified factory unit driven sensibly.

Your conversions are pretty impressive on paper, and I for one think it's a good thing they are available for those who want them, regardless if I think they are a sensible move or not. Sticking to hard facts is a good move in my book, as has been said 100,000 miles isn't particularly impressive when standard engines can reach 3 times that or more.

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R Turner

(Member)

01/09/02 06:45 AM

Re: Warning For Series Owners & New Gadget Questions Reply

Trev

Yes, performance of both the 200 & 300TDI engine can be improved by simple but effective porting work to the cylinder head. All previous evolutions of Land Rover 4 cylinder engines have responded well to this type of work without prejudicing life expectancy. To this end if a customer specified a gasflowed head on any of our exchange engines, we would offer the usual 12 months unlimited mileage warranty and expect the normal life expectancy. However a customer proposing to modify pump/ boost turbo / intercooler etc would be another matter, as it would be with Land Rover.

Gasflowing the cylinder head is a much more technically correct way of increasing efficiency. It is possible, if you have seen plenty of Land Rover cylinder heads, to see variations in standards of gasflow of new heads. Some evolutions of Land Rover cylinder head are better ported by the manufacturer, this variation clearly does not affect life expectancy, merely efficiency. However due to the expense of removing and refitting a cylinder head on what is effectively a perfectly serviceable engine, I would only really recommend head improvements where the engine is coming apart anyway.

The problem is that because it is so easy to tamper with the injection pump and turbo boost pressure and get an instant result and gratification, this tends to be the preferred option. There appears to be no real understanding of the implications which have been discussed on various forums before.

If you were to consult the professional end of the market Ie piston manufacturers/ qualified engineers associated with examining engines and components that fail for various reasons, none of them are in favour of this type of modification and will usually quote examples of Volvo's, Mercedes Benz etc where owners have damaged engines as a result of non standard settings on turbo's and/or fuel injection equipment. Indeed we have seen quite a few exchange engines ourselves damaged in this way. In all cases the owners decided to return to original settings.

The practice of interfering with electronics, boost pressure, fuelling etc is becoming a major problem to motor manufacturers and now involves the truck market. If the practice of carrying out this type of modification was completely safe, why do motor manufacturers invalidate warranty as a result of this.

Richard Turner www.turner-engineering.co.uk

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R Turner

(Member)

01/09/02 06:58 AM

Re: Warning For Series Owners & New Gadget Questions Reply

Thank you Noel. That's why we sell standard lead free cylinder heads and offer gasflowing as an option, to satisfy all requirements.

I am going to bed now.

Richard Turner

www.turner-engineering.co.uk

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RolandM

(Member)

01/09/02 11:09 PM

Re: Warning For Series Owners & New Gadget Questions Reply

Richard Several of the earliest 2.25 Power Plus engines we built have now covered miles close to 100,000 miles. As we expect, these engines are still producing the power and still use no oil between services. We expect these engines to continue performing reliabily for the next 100,000 miles.

The failure of military engines is interesting. We have also stripped many of these engines and find that major failures are almost exclusive to rebuilt engines you know the ones painted in horrible green paint. It is very rare to see a failure of the bottom end of an original Rover built engine. Closer examination of these failed engines shows that failures are almost exclusively due to assembly or other errors during the rebuilding process and not due to high RPM induced fatigue.

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RolandM

(Member)

01/09/02 11:32 PM

Re: Warning For Series Owners & New Gadget Questions Reply

Noel

Here is a good example where the Power Plus system really comes in to its own. I know we have discussed high RPM and rev limits etc and I will admit that personally the pleasure I get from running my Series IIA is from having a 33 year old vehicle which will out run modern traffic. But anyway consider the following scenario

Series IIA/ III 109" Station Wagon 2.25 pertol standard out put 120Ib.ft/68BHP its a good one!

You decide to take the family on a caravan holiday. So you load the vehicle and attach your caravan, so you have a 109 Station Wagon which weighs 2100kgs. say 450kgs for including the family of load within the vehicle and a caravan which weighs 1250kgs total 3800kgs. and you decide to head to Scotland. On the motorway. Those who have travelled with such an outfit will know the pain and embarrasement that results from having just 17.8BHP per ton yet it is all legal and Land Rover give their blessing for a train weight of 6760kgs so were not beyond limits. If you have travelled up the M6 North then you will know Shap Fell, 7 miles of up hill gradient that by the time you have reached half way you may be looking for the low ratios with lorries thundering past. Imagine the improvement an extra 30ft 16 of torque and 45BHP will make to the comfort and safety of your family all without as already explained spoiling long term reliabilty. You can add this to 2.25 by fitting ACR's Power Plus system ie. camshaft, SU carburettor kit and gas flowed cylinder heads on to the existing engine and as many have found it brings whole transformation of the vehicle capabilities.

web page

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R Turner

(Member)

01/10/02 12:54 AM

Re: Warning For Series Owners & New Gadget Questions Reply

Roland

We are getting somewhere now. But you still haven't answered the question - is it safe for Jo Bloggs to run any 30 yr old high mileage 2.25 petrol engine to in excess of 5000 revs on a regular basis without affecting the life expectancy. I am not talking about one of your rebuilt engines 2.25 - 2.8 or otherwise.

Whilst I agree that most military green engines are not particularly well built, the type of piston failures I mentioned were not connected with build quality and entirely due to operating conditions Ie stress related. Even the military cannot incorrectly assemble a piston onto a conrod. Providing the bore is the correct size, that's it. You can't blame poor assembly for piston breakage (not seizure as a result of overheating, detonation or other). So are you suggesting that a high percentage of military engines are not suitable for high performance tuning because they are badly built. I merely pointed out specific type of failure connected with operating conditions.

Now lets start thinking about original Rover built engines. Engines which have been rebuilt on a DIY basis, or by slightly less than diligent profesional mechanic who has incorrectly assembled the connecting rod bolts in a way that drags a burr down into the counter bore of the conrod. This within the normal working parameters will generally work without too much problem. However under high stress, high rpm the bolt has the potential to settle further into the counter bore, the cap works loose and the big end fails. I have seen this type of failure in a number of petrol engines over the past 20 years or so, not necessarily military. Are we to conclude that revving an engine that has been rebuilt by someone other than the military cannot fail if regularly revved in excess of 5000rpm? Or do we have to accept the possibility that some engines have the potential to fail as a result of inbuilt defect.

How do Land Rover owners determine whether their engine is suitable to be revved beyond 5000rpm which you appear to advocate as safe, or do we conclude that it is only really a good idea on a properly rebuilt engine. This would be somewhat of a shift from your original argument.

Roland, I fully accept that the risk is low, but nevertheless a tangible risk does exist. The law of physics dictates, the higher the rpm, the higher the risk.

Richard Turner www.turner-engineering.co.uk

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chris.birkett

(Member)

01/10/02 02:39 AM

Re: Warning For Series Owners & New Gadget Questions Reply

Cheers Richard / Roland

Thats cheered me up no end. I thought I'd done alright getting a 5brg recon motor in my lightweight, but now I'm not so sure.

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Noel Clark

(Member)

01/10/02 05:16 AM

Re: Warning For Series Owners & New Gadget Questions Reply

quote:

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Originally posted by RolandACR:

Imagine the improvement an extra 30ft 16 of torque and 45BHP will make to the comfort and safety of your family all without as already explained spoiling long term reliabilty.

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I think we're all agreed that the 2.25 engine was built for a different era and taking a set up like you mention up Shap probably isn't a good idea these days unless the vehicle is extremely visible, taking into account modern traffic speeds.

I think we'll have to agree to differ on the long term reliability issue, as people seem to have varying definitions of it. This takes me back to a thread on the series forum a while ago about Parabolic springs, when someone was claiming they were proven as reliable as factory originals and they had first hand experience of the superb reliability - all 36,000 miles and 18 months of it.

The only way to prove your modifications do no harm to long term reliabilty is to test one against a factory unit in an identical vehicle under controlled conditions.

[ 01-09-2002: Message edited by: NoelC ]

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Pete Johnson

(Member)

01/10/02 07:22 AM

Re: Warning For Series Owners & New Gadget Questions Reply

Richard and Roland you have both put forward excellent points and views... As Ive been reading down this post for the first time I was begining to think it would be deep reach sockets at 50 paces!!!

I have a 200tdi in a 110 and before that a ford DI in a lightweight and a 2.25 in it before that. I dont know about the products you are talking about but you mentioned the cost of head removal on a 200tdi, some time ago the lightweight with the Di was smoking a bit and doing 24mpg (130,000 on the Di) I went to a garage who tested the injectors and replaced em. After that it ran a bit rough but was told it was the pump (you could see the wear on the moving parts!!) Driving back to Manchester clouds of smoke from the exhaust had me on the phone to friends and then the head off. I cleaned all the valves and head up (what a job) and built it up again.... the short of it is a split injector... but after the clean un it went to 33mpg!!!! i tried the same on my 200tdi 110 (155,000 when i did it) and it was spotless. I was most dis chuffed as i wanted to get a better mpg (currently 24mpg) Ho hum...

Pete

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Bigfoot

(Member)

01/10/02 08:31 AM

Re: Warning For Series Owners & New Gadget Questions Reply

I have to say that this thread is fascinating - many thanks to Richard and Roland. Where else could you get such an informative and interesting debate, and retain it all in 'print' to digest at your leisure ?

Any more?

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Mike Brown

(Member)

01/10/02 05:47 PM

Re: Warning For Series Owners & New Gadget Questions Reply

Outstanding information from all concerned.

Thank you.

I agree Trev, there isn't any other place I know of where such briliant info is exchanged.

...Just a shame it no longer includes the military element from Bob Morrison...

[ 01-10-2002: Message edited by: Mike 4 mud ]

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blackpig

(Member)

01/10/02 06:46 PM

Re: Warning For Series Owners & New Gadget Questions Reply

This is a lot better than reading it in the mag!!

And no Editor to take out the big words either!

Thanks for that..

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RolandM

(Member)

01/12/02 08:11 AM

Re: Warning For Series Owners & New Gadget Questions Reply

Richard As stated on 3/1/02 we set the red line at 5200RPM on the 2.25 Power Plus engines. Obviously we also supply equipment which is retro fitted to older engines as well and customers often ask what happens to reliability? Our advice is simple, if the engine is running well, ie. consuming little oil, a minimum of ring blow by and running smoothly and quietly then the fitment of Power Plus components is recommended, if there is any doubt then spend the money getting the engine up to spec. first, by that we do not mean re-ringing, replacing bearings in situ or other patch up jobs! Experience has shown that the use of Power Plus componentson good used units has not resulted in wrecked engines just happy customers.

As for advice on RPM limits for old units who can guess? However if I was fitting parts to a used engine that I knew well, then with no hesitation I would set the limit at 5200RPM.

www.automotivecomp.com

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R Turner

(Member)

01/12/02 08:37 AM

Re: Warning For Series Owners & New Gadget Questions Reply

Thank you. We are agreed then that it is not safe to rev just any Land Rover engine to in excess of 5000rpm.

The most likely reason that there is so little trouble with performance tuning 2.25 petrols is that most owners have the sense not to drive like this as a result of the appalling fuel economy and mechanical risk that goes with this type of driving.

Richard Turner

www.turner-engineering.co.uk

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fridgefreezer

(Member)

01/12/02 08:50 AM

Re: Warning For Series Owners & New Gadget Questions Reply

I'd just like to say, without any technical terms, big words, etc. something I was told by someone very experienced in mechanical matters:

"If you drive it like a w*nker, you'll break it."

Post Extras:

G r a h a m

(Member)

01/12/02 08:53 AM

Re: Warning For Series Owners & New Gadget Questions Reply

quote:

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Originally posted by R Turner:

most owners have the sense not to drive like this as a result of the appalling fuel economy and mechanical risk that goes with this type of driving.

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...and because the sort of &quot;Person Resembling a Pink Starfish&quot; who drives like this is more likely to buy a hot-hatch Nova with a Kenlowe sticker, rather than a "cold hatch" Landy. Just my 2p worth.

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Tarzan

(Member)

01/11/02 09:30 PM

Re: Warning For Series Owners & New Gadget Questions Reply

Excellent thread all round

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rtbarton

(Member)

01/11/02 09:32 PM

Re: Warning For Series Owners & New Gadget Questions Reply

T I echo the last two posts. I am seriously considering fitting the ACR kit to a project I'm doing.

Just because I have extra power doesn't mean I'll be driving everywhere at top revs, it does mean I won't be holding the traffic up on long hills (there are plenty in Sheffield)and with a gentle right foot I would expect better economy tootling around town.

Don't forget the safety aspect of being able to accelerate out of situations too (half-shafts permitting)

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RolandM

(Member)

01/11/02 09:41 PM

Re: Warning For Series Owners & New Gadget Questions Reply

Trev Reference Performance TDi modifications.

I read with interest your debate regarding tuning TDi engines although we concentrate on petrol engines the following may be of interest.

The diesel cycle operates some what different to the petrol engine in that the term "throttle" is misleading. The diesel regarding air intake opertes at full throttle at all times ie. the power is varied by the amount of fuel injected. The reason why a diesel engine is more efficient at part load is because it is operating with high EFFECTIVE compression at all times (the petrol engine at part throttle will have its cylinders only partly filled the EFFECTIVE compression ratio may only be 2 or 3:1) High compression ratio = good economy.

If you wish to improve the output of a diesel engine, then you will need to add more fuel ie. by altering pump settings ( or the map within a computer chip on ECU controlled engines) The problem arises when you reach the point when you add more fuel than there is air available for complete combustion this becomes apparent as black smoke from the exhasut and rapid increases in exhaust temperature is often recorded. To over come this more air need to be added ie. by removing restrictions to allow freer breathing or/and increasing boost pressure from the turbo. If you increase boost pressure then the air intake temperature rises ( not good for power or reliabilty) hence the use of larger intercoolers. In fact it is possible to improve power output by amounts far greater than the engine can stand both mechanically or thermally. If you wish to improve output you will need to make adjustments carefully with the full understanding of the implications involved. I believe there is scope for improved output within the design but for long term reliability then you must be very careful not to over do it!

www.automotivecomp.com

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RolandM

(Member)

01/11/02 09:47 PM

Re: Warning For Series Owners & New Gadget Questions Reply

Roger Thank you for your comments your application is just what the ACR system has been developed for.

Cheers

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crashbox

(Member)

01/11/02 10:24 PM

Re: Warning For Series Owners & New Gadget Questions Reply

Very interesting posting by Roland, the fact that the effective compression ratio of a petrol engine varies greatly according to load is not widely understood but is important. Valve timing also affects the true CR of an engine, since at low engine speeds at least, the actual volume of compressible mixture (or air on a diesel) you can achieve depends on how far up the cylinder the piston is when the inlet valve closes. Thus a petrol engine with "hot" cam timing and a high compression head will have poor torque at low revs but will go like the clappers at the speeds the engine is optimised for. Tuning mods on a LR engine have to be relatively mild, since you cannot afford to lose low speed flexibility. I would bet that a lot of the power increase on the ACR kit comes from the SU carb and the fact that the charge density is higher as the inlet manifold is not getting all the heat input from the exhaust that a standard set up does. This lower induction temp also allows a higher CR without detonation on the same octane fuel.

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rtbarton

(Member)

01/11/02 11:41 PM

Re: Warning For Series Owners & New Gadget Questions Reply

quote:

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Originally posted by RolandACR:

Roger Thank you for your comments your application is just what the ACR system has been developed for.

Cheers

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Discount please!

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R Turner

(Member)

01/12/02 12:08 AM

Re: Warning For Series Owners & New Gadget Questions Reply

quote:

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Originally posted by crashbox:

Thus a petrol engine with "hot" cam timing and a high compression head will have poor torque at low revs but will go like the clappers at the speeds the engine is optimised for.

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Crashbox

You sound like you know what you are talking about. Would you like to venture an opinion as to what happens to an engine's efficiency, pertaining to hydro carbon emissions and idling characteristics.

Richard Turner

www.turner-engineering.co.uk

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Brett1

(Member)

01/12/02 12:35 AM

Re: Warning For Series Owners & New Gadget Questions Reply

quote:

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Originally posted by R Turner:

Crashbox

You sound like you know what you are talking about. Would you like to venture an opinion as to what happens to an engine's efficiency, pertaining to hydro carbon emissions and idling characteristics.

Richard Turner

www.turner-engineering.co.uk

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I think the gauntlet has just been thrown down!

Brett

[ 01-11-2002: Message edited by: Brett Hurrell ]

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crashbox

(Member)

01/12/02 01:19 AM

Re: Warning For Series Owners & New Gadget Questions Reply

Engine efficiency in a petrol engine will be at it's highest if you can completely burn the fuel at a lean A/F ratio, and using the highest C.R. for a given octane fuel. Hydrocarbon emissions and idling quality are inter-related. A "hot" tuned engine will most likely have a lot of valve overlap. Good for "scavenging" at high revs, but not good for emissions or fuel economy. If the inlet valve opens much before TDC, exhaust gas can escape into the inlet port and contaminate the fresh mixture. This gives rough idling and you have to set the mixture extra-rich in order to be able to burn it. The overlap allows unburnt mixture to escape straight out of the exhaust port, where it partially burns with the exhaust gas. Fuel is wasted without producing power and HC emissions go through the roof. On a diesel overlap does not pollute as you are only dealing with air, not fuel mixture, but the timing still needs to be optimised for the speed range of the engine.

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R Turner

(Member)

01/12/02 02:36 AM

Re: Warning For Series Owners & New Gadget Questions Reply

Crashbox - Excellent could not have put it better myself.

There is however somewhat more to this than meets the eye. It is not just a question of convincing the MOT tester or worrying about costs of fuel consumption. When an engine runs rich, unburnt fuel causes various internal effects such as abnormal valve guide wear, abnormal piston ring wear, and as a result of the degredation of engine oil, camshaft/follower wear. This will ultimately reduce life expectancy and increase operating costs.

I think we can now conclude that this "hot" engine format when run at it's optimum speed Ie high rpm will increase mechanical stress and fuel consumption. Low operating speeds outside of the optimum speed will be inefficient, sluggish and costly in fuel consumption and resulting excessive engine wear.

Bearing in mind the life expectancy of a 2.25 petrol under favourable operating conditions is 3 to 400.000+ miles. Ie 30 to 40 years at average 10.000 miles annually.

Next question:-

We want to achieve maximum miles per gallon, improve driveability (torque), especially at low rpm, reduce the speed at which max. BHP is achieved, reduce HC emissions, run on premium unleaded and improve life expectancy. How can this be best achieved without increasing compression ratio.

Richard Turner

www.turner-engineering.co.uk

PS - good to see people participating!

[ 01-11-2002: Message edited by: R Turner ]

Post Extras:

crashbox

(Member)

01/12/02 04:26 AM

Re: Warning For Series Owners & New Gadget Questions Reply

quote:

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Originally posted by R Turner:

Next question:-

We want to achieve maximum miles per gallon, improve driveability (torque), especially at low rpm, reduce the speed at which max. BHP is achieved, reduce HC emissions, run on premium unleaded and improve life expectancy. How can this be best achieved without increasing compression ratio.

Richard Turner

www.turner-engineering.co.uk

PS - good to see people participating!

[ 01-11-2002: Message edited by: R Turner ]

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Richard, I think I know where this is leading, but here goes:-

If you specifically exclude increasing the C.R. (although I would for the thermal efficiency gain), you are basically left with improving the volumetric efficiency.

To run on 95 RON U/L fuel you need to fit suitable valve seats, and possibly guides.

While doing this you can get the engine to breathe better by employing three angle valve seats & tidying up obstructions in the ports, which you just happen to do on your "performance" heads.

If you want economy & low speed torque the standard camshaft with only 29/30* overlap must stay. Looking at the 3 brg 2 1/4 petrol valve timing, possibly advancing the cam by a FEW degrees might give a little more torque as the inlet valve will close earlier. You may also gain in reduced pumping losses by the opening of the exhaust valve a little earlier too, as the LR petrol exhaust valve opens very late even for a "slogging" engine. (I assume the reason for this was to give the 24* of exhaust lag to try and maintain the torque at higher speeds). This could improve economy. Take it too far though and you contaminate the fuel mixture with early Inlet opening. So far we've got the engine to breathe a bit better at low speeds. Not very sexy maybe, but think about the speed range a typical series Land Rover engine may be used over. It idles at ~500 RPM, with 7.50 tyres and O/D 60 MPH is 2850 RPM. A sensible maximum road speed in a leaf-sprung model can't be over 75 MPH, and this eqates to 3,500 RPM in O/D top. So really it's pointless in having the peak power much above this speed if economy and long life is your priority. Remember when series 2 Land Rovers first came out they didn't have overdrives so at 70 MPH the engine would be running at 4,250 RPM (on 7.50's). The engine needed to peak at this RPM in order to provide the power to overcome the aerodynamic drag. If you raise the gearing (5 speed box/overdrive) then you need more torque but at a lower speed to take advantage of it. From my point of view you want something which will pull from idle, plenty of torque - peaking at about 2,000 RPM, and a power peak of about 3,500. The big spin-off of keeping engine speeds low is that mechanical stress is reduced as it increases with the square of speed, so the components in an engine running at 5,200 RPM are under 2.2 times the stress of the engine peaking at 3,500.

Question for you Richard:- Why don't you favour increasing the C.R.?

Post Extras:

abkelly

(Member)

01/12/02 11:39 AM

Re: Warning For Series Owners & New Gadget Questions Reply

This thread really is an eye opener, considering that I will be facing an unleaded head conversion this year.

Alan S2A

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Bigfoot

(Member)

01/12/02 05:46 PM

Re: Warning For Series Owners & New Gadget Questions Reply

Yep - good thread and it continues

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R Turner

(Member)

01/13/02 08:57 AM

Re: Warning For Series Owners & New Gadget Questions Reply

quote:

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Originally posted by R Turner:

[QB]

Next question:-

We want to achieve maximum miles per gallon, improve driveability (torque), especially at low rpm, reduce the speed at which max. BHP is achieved, reduce HC emissions, run on premium unleaded and improve life expectancy. How can this be best achieved without increasing compression ratio.QB]

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Crashbox

If we are to meet the above criteria, this rules out hot cams and non standard carburettors and leaves us with one option which as you rightly say - improve efficiency. How do we do this? We thoroughly gasflow the exhaust and inlet ports on the cylinder head. This is time consuming and means considerable time spent grinding material out of the ports. Most people choose the compression ratio route rather than spend the time required to gasflow the head properly.

Q - What does all the gasflowing achieve on a 2.25 petrol.

A - 120ft lbs of torque at 2750rpm. 70bhp at 3300rpm.

This test was conducted regularly on 2.25 petrol engines on a calibrated Heenan & Froud G3 Dynomometer. The engines tested were newly built and not run in and therefore still not realising their optimum potential and may well have produced more impressive sounding figures had we looked for power higher up the rev range. All ancillaries fitted were standard, standard camshaft, premium unleaded fuel.

OK the above does not sound like an improvement does it, until you start talking to customers and driving the things.

Example 1

S111 LR SWB high ratio diffs, standard carb (Zenith) & ignition, 8:1 gasflowed head. Prior to conversion usual cruising speed 50mph. After conversion driver reported significant improvement in driveability. Described as, using the same throttle input to achieve 50mph previously, now produced 70mph. He now cruises at 55mph at a significantly lighter throttle opening. Better hill climbing and towing Ie pulls higher gears at lower revs and as a bonus has improved fuel economy.

Example 2

LWB Safari LR, 8:1 gasflowed head, ACR SU carb & manifolding. Regularly outperforms S2a SWB with the full ACR setup IE carb, manifold, camshaft, 9:1 head. Is however just within MOT HC limits.

Example 3

Jim Allen, writer for LRO early 90's. Feature LRO May 1991. Supplied 2.25 long engine with gasflowed head, 2.5 petrol camshaft. Fitted externally with a 4 into 1 tubular exhaust, a custom built low restriction exhaust system (oversize pipes and freeflow muffler) a Weber 28-32DGV twin choke carb on a Pierce manifold and a late style Lucas 45D distributor with luminition electronic ignition and K&N airfilter. How did it perform. "in my case all the modifications added up to a rip snorting 2.25, hill climbing on the highways is light years better than before. Hills that once required 3rd or lower can now be pulled at top gear at close to the speed limit. Top speed has increased to well past 80mph because the rpm range and power curve is extended significantly." Jim's opinion was "as far as how my engine turned out I can make a subjective evaluation, since the twin choke carb, exhaust modifications and ignition were installed on the previous engine which also had a fairly fresh valve job. The increase in power must be due to the modified cylinder head and 2.5 camshaft and a good rebuild. The Turner high performance head is ported with emphasis on the exhaust side. Cylinder head modification is a situation where a little work done in the right places reaps more benefits than a lot of work in the wrong place".

Example 4

Customer booked in a 110 LR to be converted from a turbo diesel engine to a 2.5 petrol. The engine was built to our normal standard, 8:1CR gasflowed head, new carb & distributor, produced 83bhp at 3300rpm and 135ft lbs of torque at 2750rpm. This vehicle was road tested and easily reached an indicated 90mph and would still pull 80mph on slight inclines.

Example 5

Ex para trooper owns LWB S111, specifies 5mb 2.25 petrol to be fitted. 2.5 camshaft, Zenith carb, gasflowed 8:1CR head, electronic ignition. Reported speeds in excess of 80mph achievable.

All this without having to resort to compression ratio changes. Why don't we favour increasing the compression ratio.

1. How do you predict the exact compression ratio. Not too difficult to work out on a new engine, but as bore sizes increase with rebuild, compression ratio increases.

2. At Turner Engineering we mass produce cylinder heads, which can be sold anywhere in the world. 8:1 has given tremendous results in it's gasflowed format over the past 17 years. Fuel quality varies around the world. How does one determine advice to give to a customer in Bangladesh for example as far as timing is concerned.

3. Insurance companies are not keen on compression ratio changes.

4. Most cylinder heads will ultimately be supplied to customers with engines, carbs, ignition systems, radiators etc which have been in service for some years and may not be as efficient as they should be. This would give the potential for problems with setting up the engine. Increased heat output via the cooling system that is past it's best then has the potential to become a problem.

5. Due to the potential for detonation with higher compression ratio's and that an 8:1 gasflowed head will happily run at 6 degrees BTDC without problems, we have to be aware of the potential where owners can make mistakes in overly retarding or advancing the ignition. Not to mention faulty distributors and or carburettors. We do not want complaints concerning failed head gaskets, melted pistons or other types of engine failure associated with abnormal combustion temperatures.

6. There are geometric problems. When skimming a large amount of the cylinder head, the push rods can end up too long and adjustment on the tappets runs out, requiring shims. Head bolts can bottom out, reducing torque to the head resulting in head gasket failure. Head may 'jack up' on the waterpump. You may not be able to skim the head again if it requires service in the future.

Conclusion:

The fact is that a 8:1CR head format for all intents and purposes under reasonable operating conditions is 100% reliable, gives outstanding performance in a gasflowed format and generates virtually no queries. Do we want to take the risk of increasing complaints by supplying a 9:1CR head, other than for competition use, or to clients who can properly set up an engine using new ancillaries and can carry out the correct adjustments to tune in a non standard carburettor should they choose that route.

Clearly there is a market for high compression heads and bolt on ancillaries. Logic however dictates this format is more suited to competition use or where life expectancy and/or fuel economy is of secondary importance.

Our philosophy has been to offer the day to day motorist improved performance and economy at little more than the cost of a standard lead free cylinder head. But this gasflowed cylinder head supplied in a 9:1CR format and used with non standard ancillaries will outperform anything on the market and has performed extremely well in competition. This is not particularly well known due to the fact that we have not particularly tried to market this type of product due to the time required in explaining the in's and out's to potential customers. Our work load these days is geared towards the later diesel engines.

Next question:

Care to venture an opinion as to why the 8:1CR gasflowed head performs so well. What is actually going on from a technical point of view.

Richard Turner

www.turner-engineering.co.uk

[ 01-12-2002: Message edited by: R Turner ]

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Miserableolgit

(Member)

01/12/02 09:18 PM

Re: Warning For Series Owners & New Gadget Questions Reply

quote:

--------------------------------------------------------------------------------

Originally posted by abkelly:

This thread really is an eye opener, considering that I will be facing an unleaded head conversion this year.

Alan S2A

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Yep, excellent stuff! Obviously it's just a bit too early to nominate this for the 2002 Thread of the Year award but it certainly should be in the running!

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rtbarton

(Member)

01/12/02 09:34 PM

Re: Warning For Series Owners & New Gadget Questions Reply

When I do finally get my project on the road I'll be able to make an informed opinion as to what to do with the engine.

Is it too early to ask about LPG? The foregoing arguments mainly relate to petrol.

Is there a case for going to 8.5:1 CR?

Post Extras:

crashbox

(Member)

01/13/02 03:18 AM

Re: Warning For Series Owners & New Gadget Questions Reply

Richard, firstly if I've appeared to belittle the amount of modification that goes into your gasflowed heads then I apologise. I've seen one in progress so I know a lot of work goes into them.

From a technical point of view, you are optimising the flow capability of the port, although it is a complex subject with many variables. Obstructions like the valve guides and casting nibs etc reduce the cross sectional area of the port. No doubt you have found it beneficial to open the port a little where it's flow is not optimum. Obstructions cause turbulence in the gas flow, which you do not want in the exhaust as it hinders the escape of waste gas out of the cylinder. If you can get the cylinder to exhaust freely you reduce pumping losses and facilitate drawing in the fresh charge by creating a depression. A free flowing induction port gives a high volumetric efficiency even with short cam timing, so there's more charge to compress in the cylinder. Provided you can maintain the fuel droplets in suspension in the induction tract, the engine should run smoothly & deliver good economy.

One area where I'd disagree with you up to a point is the issue of C.R.'s, although I can understand your commercial reasoning of selling a "hassle-free" product. I have a 2 1/4 petrol which was unleaded and skimmed by yourselves, but was not gasflowed. With +.020 pistons fitted I reckon the C.R. to be approximately 8.8:1 It has performed very satisfactorily with no problems with detonation or running on at all. Actual power output is not that noticeably higher, but it pulled strongly at low speed & with improved fuel economy - what I set out to attain. I believe that the reduced clearance volume of the skimmed head improves V.E. as well as giving higher compression pressures anyway.That head will be transferred to my series 2 and one future modification will be to weld shut the open top of the exhaust hotspot in order to reduce intake temperatures & increase charge density. This should help offset the risk of detonation with the higher C.R. As I like tinkering about the trial and error setting necessary to get the best out of a non standard set up is no bother, the book figures are only a starting point.

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jwriyadh

(Member)

01/13/02 04:39 AM

Re: Warning For Series Owners & New Gadget Questions Reply

Richard,

I understand you sticking to standard carburettors to remove the setup problems but do you not agree t

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