Poor performance 110 200tdi

[Jocklandjohn]

1 minute ago, Maverik said:

I'd wager, the combined knowledge of this forum would be able to beat a fair few experts.

Indeed!

[monkie]

I would start by looking at the lift pump. I have been very lucky with them, but have now gone electric. Other members on here have reported even with Delphi ones that they just don't seem to last, so if you last looked at this 3 years ago then it is worth going straight to this even if it is just to rule it out.

[Maverik]

ok so just read the topic top to bottom - you say you're running a hybrid turbo? not standard? - any details?

Also, has this engine always had this problem? or did it suddenly just start? - you say you've had the problem a long while?

I've always had 200's, so had a fair bit of fixing over the years.

When I had going up hill trouble - it was down to the boost pressure being set on the low side - she was fine on the flat but show her a hill and the power would fall off.

Another low power issue I also suffered was a stuck boost compensator pin (as also outlined above).

 

Considering its smoking on pushing the accel pedal going up hill, I'd say the engine is being over-fueled for the air going in. which could mean you're not getting enough air... so back to the turbo and inlet.

There's a few tests you can do by going for a drive with various air hoses removed.

[Nonimouse]

17 minutes ago, Maverik said:

 

 

Considering its smoking on pushing the accel pedal going up hill, I'd say the engine is being over-fueled for the air going in. which could mean you're not getting enough air... so back to the turbo and inlet.

There's a few tests you can do by going for a drive with various air hoses removed.

I think this is where you have to start. Remember a collapsing hose isn't easy to spot

I don't think it's fuel delivery as it's smoking - sounds like air restriction.

Do check the timing though - go back to factory marks and start again

I'm also one of those 200tdi folk who go gently steaming past you on the hills (metaphorically) {Disco, with 1.22:1 box and 235/85x16's 

[Jocklandjohn]

56 minutes ago, Maverik said:

ok so just read the topic top to bottom - you say you're running a hybrid turbo? not standard? - any details?

Also, has this engine always had this problem? or did it suddenly just start? - you say you've had the problem a long while?

I've always had 200's, so had a fair bit of fixing over the years.

When I had going up hill trouble - it was down to the boost pressure being set on the low side - she was fine on the flat but show her a hill and the power would fall off.

Another low power issue I also suffered was a stuck boost compensator pin (as also outlined above).

 

Considering its smoking on pushing the accel pedal going up hill, I'd say the engine is being over-fueled for the air going in. which could mean you're not getting enough air... so back to the turbo and inlet.

There's a few tests you can do by going for a drive with various air hoses removed.

Hybrid turbo (recommnded by, and fitted by Roland Marlow at ACR when he overhauled the engine a decade ago, and who at that point judged everything to be in tiptop condition as it had been carefully used and serviced by me with regular oil & filter, every 4k miles).  Dont know much about the type or spec of turbo though, although he assured me its good for significantly higher BAR than standard, up to 1.25, I'm running just on 1.1 currently.

Its always been sluggish, and as I've added various camper-related bits and incresaed its weight its not helped. I did the various alterations along the way to try to resolve it, new intercooler, hoses, injector service, Turner performance head etc, and recently fitted a boost gauge and discovered turbo boost was set far too low (I think it may have been altered by the Bosch pump service folks when they were trying to resolve the mad smoking after the pump overhaul which turned out to be the stuck out fuel pin) and I've upped boost to its current setting which has helped a lot but has still not fully resolved the issue.

 

1 hour ago, monkie said:

I would start by looking at the lift pump. I have been very lucky with them, but have now gone electric. Other members on here have reported even with Delphi ones that they just don't seem to last, so if you last looked at this 3 years ago then it is worth going straight to this even if it is just to rule it out.

I actually have a spare one under the seat as I went through 5 in 7 years, and now carry a spare one just in case although this one *seems* ok, but you're right its a fairly cheap test to see what happens. Will certainly do that.

 

 

36 minutes ago, Nonimouse said:

I think this is where you have to start. Remember a collapsing hose isn't easy to spot

I don't think it's fuel delivery as it's smoking - sounds like air restriction.

Do check the timing though - go back to factory marks and start again

I'm also one of those 200tdi folk who go gently steaming past you on the hills (metaphorically) {Disco, with 1.22:1 box and 235/85x16's 

 

I'll need to get back in about the air intake hoses as maybe I've missed a delaminating one. The ones from base of snorkel to intercooler are still original as far as I recall.

I'm going to get the timing belt replaced and all the timing checked over next month, and in the menatime I'll check over the intake tract in fine detail, and also as previously suggested disconnect inlet stuff before the turbo and take it for a short run and see whether the full flow air helps.

[muddy]

Im sure you are more than capable of tackling a cam belt change/check.

 

You can use an R380 reverse light switch as a locating pin screwed into the wading plug hole in the flywheel housing (spy through or feel for the largest slot) to set the crank at tdc then try a 9.5mm drill into the pump through the FIP inspection hole. there's a 20 min check of FIP to crank timing. 

[western]

On a 200tdi the flywheel timing slot is the Narrow of the 2 slots 

[Jocklandjohn]

5 hours ago, muddy said:

Im sure you are more than capable of tackling a cam belt change/check.

 

You can use an R380 reverse light switch as a locating pin screwed into the wading plug hole in the flywheel housing (spy through or feel for the largest slot) to set the crank at tdc then try a 9.5mm drill into the pump through the FIP inspection hole. there's a 20 min check of FIP to crank timing. 

I've always been wary of the timing because its one of those things thats easy to get wrong (as my experience with 'proper' mechanics has revealed!) but may result in dire consequences! But I guess its not much harder than swapping a head! The lad who I've spoken to about doing it for me is a small operation so I may be able to watch and learn as he does it.

29 minutes ago, western said:

On a 200tdi the flywheel timing slot is the Narrow of the 2 slots 

 

I seem to recall getting into this years ago and finding that there was more than one slot and got thoroughly perplexed as I realised it was less straightforward than I thought and I could be 180 deg out! 

 

Watch this space...!

[Maverik]

I just wonder if you're getting a bit of a "perfect storm" type thing going on. Just thinking through some of these points...

Gearing: from experience 110's of this era had in my opinion a great gearbox ratio set-up compared to some later Td5 gearbox gearing i.e. - it was on the taller side, you've now upped the Transfer box output making the gearing even more "taller".

Turbo: you've got a non standard turbo fitted that I'm guessing has a different compressor blade profile which will shift the power delivery curve - making some assumptions this might have shifted the peak power up the rev range...

Your truck loading:  You've mentioned you've got some living gear installed in the truck, so its running with a certain installed extra equipment...

I'm just thinking that you actually might not have got anything wrong with the engine, but just factoring in all the above elements, you might have shifted the optimum operation of your truck outside the engines "happy place"... - which would kind of account for why she dies on hills, you've shifted the peak power to a higher rev range, so you have to drop gears like mad to keep the revs up to where the torque is...

My Camel 110 is 200tdi 1991 and its standard engine/transmission - she's heavy with a full internal roll cage and winch and roof rack etc. but I never had a problem with the standard transmission/engine set-up. yeah you had to drop a gear on the hills and take a run up but she cruised pretty happily at 60mph...

[Jocklandjohn]

Before I had the work done I spoke with Roland at ACR and explained I'd wanted a more relaxed cruising than the 1:4 box but was concerned the 1.2 Disco gears might be too tall, given I was sticking some camping gear inside (mostly light ply and plastic boxes to be fair) so not really adding much more weight than a CSW would have with additional seats and doors.

My lifting  roof gubbins is pretty much the same weight as a roof rack & roof tent, so I'm pretty much in the normal weight range for a 110. He advised the hybrid turbo as being appropriate. I also had a word with Ashcrofts about it because when the engine was overhauled I got a recon transfer & gearbox from them and chose the Disco gearing, and they too were of the opinion this would be a suitable option.

Possible though that the gearing is the difference. Maybe I'm going to have to go back to the original gear set. 

I'm getting the expert to look it over and give me an opinion in a couple of weeks so I'll report back on the outcome.

[Nonimouse]

Interesting thought though.

I've noticed that there is always a 'Rob Peter, to pay Paul' set up with tuning 200tdi's properly. Unless you fit a boost pin and essentially throw in as much diesel as it will burn, whilst watching the rest dissapear into the environment.

Running a 200tdi with the same gearing but with a standard turbo (at standard boost) tweaked boost fuelling and a slightly bigger intercooler, I do sometimes have to change down a gear when towing over 2 tonnes - sometimes two when pulling 3.5tonnes. My vehicle isn't overloaded and weighs in at about 2.1 tonnes...

Where I suffer is reversing up slopes when off boost - dead like a dog. Had the same thing with the last 5 200tdi's (4 vehicles) all set up the same way, but one had 1.44 gears...

If it is the 'perfect storm' then setting as much back to standard settings , as possible, might be the way. Might I also suggest a chat with Ian Braughan form IRB or Jermey Fern. Roland is more a petrol tuning and dodgy manifolds kind of guy...

*please note, the dodgy mainifolds is a tongue in cheek comment and in no way an accusation the Roland or his company sell dodgy mainifolds for four cyclinder petrol engines. 

 

[Peaklander]

However there is a lot of black smoke, as @Jocklandjohnpointed out when I mentioned the clutch. Wouldn’t that imply an imperfect fuel/air mix when pushing power to go uphill?

[rusty_wingnut]

I've read this with a wry smile, I would wager that you've got a number of factors combining to cause an issue but here are some ideas I have:

 

1) 1.2 transfer box is too high for a defender IMO - my old 300 90 wouldnt pull it on anything but a flat motorway. Having said this my 110 feels like it could manage, but every now and then when towing I think better of it!

2) you have a VNT ( unless I am misreading?) Again I had a VNT on my 90 and it was great for low down grunt but top end I never felt it was quite as good as a standard turbo.

3) I would say that although you've got new hoses you still need to check if you have a leak - new hoses dont mean uanything if they're leaking

4) Check if your intercooler is leaking, again because it's new or fancy doesn't mean it isn't leaking.

5) Check you have some lobes on your camshaft, again I've seen a couple of TDIs with barely any valve movement and this leads to poor performance.

6) Have you got a leak on the boost pipe from turbo to FIP? Similarly is your VNT actuated with a diaphragm has it got a hole?

7) Valve timing is worth a check as mentioned.

 

With respect I've seen a lot fo engines overhauled by experts and my opinion is that you are better doing it yourself and knowing it's right. This experience isn't just in Land Rovers, but also in my other vehicular interests. I viewed a 2ltr powered Series 1 recently that was restored and engine upgraded for performance etc, I was told the engine was built by an absolute specialist with years more experience than me, better cleaner worksho etc, and frankly when I drove it I was underwhelmed.

[Jocklandjohn]

1 hour ago, Nonimouse said:

Interesting thought though.

I've noticed that there is always a 'Rob Peter, to pay Paul' set up with tuning 200tdi's properly. Unless you fit a boost pin and essentially throw in as much diesel as it will burn, whilst watching the rest dissapear into the environment.

Running a 200tdi with the same gearing but with a standard turbo (at standard boost) tweaked boost fuelling and a slightly bigger intercooler, I do sometimes have to change down a gear when towing over 2 tonnes - sometimes two when pulling 3.5tonnes. My vehicle isn't overloaded and weighs in at about 2.1 tonnes...

Where I suffer is reversing up slopes when off boost - dead like a dog. Had the same thing with the last 5 200tdi's (4 vehicles) all set up the same way, but one had 1.44 gears...

If it is the 'perfect storm' then setting as much back to standard settings , as possible, might be the way. Might I also suggest a chat with Ian Braughan form IRB or Jermey Fern. Roland is more a petrol tuning and dodgy manifolds kind of guy...

*please note, the dodgy mainifolds is a tongue in cheek comment and in no way an accusation the Roland or his company sell dodgy mainifolds for four cyclinder petrol engines. 

 

*noted!

I'll get an expert opinion in a  couple of weeks - timing belt was due for change anyway so its a good time to have the whole thing timed up and work from there. In the meantime I can check al the hoses and see if there's anything that my previous poking about has missed.

[Jocklandjohn]

2 hours ago, rusty_wingnut said:

I've read this with a wry smile, I would wager that you've got a number of factors combining to cause an issue but here are some ideas I have:

 

1) 1.2 transfer box is too high for a defender IMO - my old 300 90 wouldnt pull it on anything but a flat motorway. Having said this my 110 feels like it could manage, but every now and then when towing I think better of it!

2) you have a VNT ( unless I am misreading?) Again I had a VNT on my 90 and it was great for low down grunt but top end I never felt it was quite as good as a standard turbo.

3) I would say that although you've got new hoses you still need to check if you have a leak - new hoses dont mean uanything if they're leaking

4) Check if your intercooler is leaking, again because it's new or fancy doesn't mean it isn't leaking.

5) Check you have some lobes on your camshaft, again I've seen a couple of TDIs with barely any valve movement and this leads to poor performance.

6) Have you got a leak on the boost pipe from turbo to FIP? Similarly is your VNT actuated with a diaphragm has it got a hole?

7) Valve timing is worth a check as mentioned.

 

With respect I've seen a lot fo engines overhauled by experts and my opinion is that you are better doing it yourself and knowing it's right. This experience isn't just in Land Rovers, but also in my other vehicular interests. I viewed a 2ltr powered Series 1 recently that was restored and engine upgraded for performance etc, I was told the engine was built by an absolute specialist with years more experience than me, better cleaner worksho etc, and frankly when I drove it I was underwhelmed.

Thats a good list to be going on with! Thanks for the pointers.

Edited September 29, 2021 by Jocklandjohn

[monkie]

This is a very interesting thread with some interesting thoughts. Please update us when the issue(s) is found. 

[Jocklandjohn]

10 hours ago, monkie said:

This is a very interesting thread with some interesting thoughts. Please update us when the issue(s) is found. 

Yes I certainly will.

One other thing I read when looking for solutions (on here, but cant recall author) was the actual symptoms of advanced/retarded timing. Author remarked that if the FIP pump is retarded the engine sounds smoother but EGT´s go up a lot, you lose power (and get worse MPG). Author noted also that running on the flat might be fine but hills will be where the lack of power is revealed, and also that with retarded timing the actual engine running temp. can be noticeably 'cooler'. When advanced, the engine sounds noisier or with a knocking sound when revving it from idle but runs 'hotter' and the 'sweet' spot of FIP timing will have some knock, lower EGT's and correct coolant temps, but good power delivery.

Is this correct ?

Am I right to assume that this is because incomplete combustion in the bores means less power, which = less heat, but the fuel thats not burnt will when chucked into the exhaust manifold cause some temp increases there?

I have exactly these symptoms, engine is smooth as silk, my EGT's can get high very quickly when off boost; and once engine is warmed up properly and running along at 50mph the engine coolant temp gauge (digital type) drops from 80/83 deg to a steady 73-75 deg. I've read that these engines are known to run 'cool' but this seems rather cooler than is normal. 

So might this suggest FIP timing anomaly? 

[monkie]

Yes, the fuel injection timing does have dramatic effects to the running and ease of starting. You can adjust the pump timing without taking the belt off. Set the crank to Tdc, the pump timing pin should slide in easy. If not you can slacken the pump pulley screws adjust the pump timing whilst the pulley stays static until the pin slides in easy then tighten the screws back up. 

[Mo Murphy]

John,

For comparison purposes, my 200 tdi.

Aftermarket fuel pin

Boost maximum 1.2 bar

Allisport big intercooler 

Standard turbo

1.4 transfer gearing with 33" MT tyres

Standard genuine thermostat

Standard FIP timing

New timing belt done by myself so I know its spot on (as mentioned above, I always take the radiator out so I can see what I'm doing)

 

Normal running temp. 92-94°C

EGT @ steady 60-65mph, 400-500°C, 0.5 bar boost approx on the flat

Fuel economy at above, 26-27 mpg

Doesn't slow significantly for hills.

HTH

Mo

 

 

[Jocklandjohn]

2 hours ago, monkie said:

Yes, the fuel injection timing does have dramatic effects to the running and ease of starting. You can adjust the pump timing without taking the belt off. Set the crank to Tdc, the pump timing pin should slide in easy. If not you can slacken the pump pulley screws adjust the pump timing whilst the pulley stays static until the pin slides in easy then tighten the screws back up. 

Yes thanks, I've had a look at the various posts on here about that recently. I was really surprised at how much difference a VERY little rotation makes to engine performance, but also the EGT's. 

 

1 hour ago, Mo Murphy said:

John,

For comparison purposes, my 200 tdi.

Aftermarket fuel pin

Boost maximum 1.2 bar

Allisport big intercooler 

Standard turbo

1.4 transfer gearing with 33" MT tyres

Standard genuine thermostat

Standard FIP timing

New timing belt done by myself so I know its spot on (as mentioned above, I always take the radiator out so I can see what I'm doing)

 

Normal running temp. 92-94°C

EGT @ steady 60-65mph, 400-500°C, 0.5 bar boost approx on the flat

Fuel economy at above, 26-27 mpg

Doesn't slow significantly for hills.

HTH

Mo

 

 

Very helpful Mo. Especially the 92-94 deg. I rarely see that!

This is curious because my heater (cab) temps have been low too for some time as well, and despite following Western's tips for heater adjustment, including removing the heater assembly and flushing the matrix, replacing foams on the flaps and lubricating all the pivoting bits, its still been somewhat down on temp, suggesting (I now assume) it may be as a consequence of the lower engine operating temps?

I'm not sure who did it but my turbo boost was wound way back, to the point it was actually barely working. It may have been the Bosch guys trying to solve the excess smoking and REALLY carp performance  (which we finally discovered was the stuck-out fuel pin which occurred during their overhaul of it and which escaped their notice) but once I'd fitted a boost gauge it was easy to spot what was (not) going on. So I then started to increase the boost a bit at a time and got to the (current) point where 5th gear was actually usable (!) again - running 1.1 BAR . I tried a tad further but although it went a little bit better, the EGT's were easy to get ott so I came back down. But even so, despite these improvements on the flat, hill hauling was still not great. 

I also get a 'restricted' sensation when accelerating - almost like a rev limiter. It 'feels' like the engine wants to keep going but it just hits this wall and I have to change up. Noticeable in 2nd gear pulling away, hit the 'dead' zone and have to change to 3rd but finding 3rd is not quite providing enough 'oomph' to haul it on as I'd expect. I can hear the turbo whistling in lower gears as I amble about, and altering as I'd expect it to with throttle movement etc. so this might be a fueling issue.

 

 

Edited September 30, 2021 by Jocklandjohn

[Maverik]

56 minutes ago, Jocklandjohn said:

Yes thanks, I've had a look at the various posts on here about that recently. I was really surprised at how much difference a VERY little rotation makes to engine performance, but also the EGT's. 

 

Very helpful Mo. Especially the 92-94 deg. I rarely see that!

This is curious because my heater (cab) temps have been low too for some time as well, and despite following Western's tips for heater adjustment, including removing the heater assembly and flushing the matrix, replacing foams on the flaps and lubricating all the pivoting bits, its still been somewhat down on temp, suggesting (I now assume) it may be as a consequence of the lower engine operating temps?

I'm not sure who did it but my turbo boost was wound way back, to the point it was actually barely working. It may have been the Bosch guys trying to solve the excess smoking and REALLY carp performance  (which we finally discovered was the stuck-out fuel pin which occurred during their overhaul of it and which escaped their notice) but once I'd fitted a boost gauge it was easy to spot what was (not) going on. So I then started to increase the boost a bit at a time and got to the (current) point where 5th gear was actually usable (!) again - running 1.1 BAR . I tried a tad further but although it went a little bit better, the EGT's were easy to get ott so I came back down. But even so, despite these improvements on the flat, hill hauling was still not great. 

I also get a 'restricted' sensation when accelerating - almost like a rev limiter. It 'feels' like the engine wants to keep going but it just hits this wall and I have to change up. Noticeable in 2nd gear pulling away, hit the 'dead' zone and have to change to 3rd but finding 3rd is not quite providing enough 'oomph' to haul it on as I'd expect. I can hear the turbo whistling in lower gears as I amble about, and altering as I'd expect it to with throttle movement etc. so this might be a fueling issue.

 

 

Can you take a few photos of your engine? - I'm intrigued to see your turbocharger and induction set-up.

If you have a VNT turbo - they work in a different way to a standard turbo and if the vane modulator has been faffed with this will have an effect on what its doing. - My Turbotechnics VNT is set to "boost" at 1.25 - 1.45 bar actuation range. - this I got from Pete Bell at Bell Auto who makes the Alisport VNT kit.

 

[Jocklandjohn]

1 hour ago, Maverik said:

Can you take a few photos of your engine? - I'm intrigued to see your turbocharger and induction set-up.

If you have a VNT turbo - they work in a different way to a standard turbo and if the vane modulator has been faffed with this will have an effect on what its doing. - My Turbotechnics VNT is set to "boost" at 1.25 - 1.45 bar actuation range. - this I got from Pete Bell at Bell Auto who makes the Alisport VNT kit.

 

Can get some pictures when I get home - currently away for several days.

Afaik its not a VNT just a 'hybrid'. When I was resolving the fuel pump issues and trying to establish some baseline settings I emailed Roland who supplied/installed it to get some details and he replied:

 

The turbo will
have a different trim on the compressor, and a better material
for the exhaust turbine, able to stand more heat. its more
tailored for reliable higher output from the engine.

The turbo will run safely at boost up to 18 PSI. However, every
PSI of boost you add will reduce fuel efficiency due to higher
exhaust back pressure and also load the bearings more, so use
the lowest boost you can to do the job.

As an on the road indicator, a clean exhaust at a steady high
PRM, maximum load, such as climbing a steep hill with a load is
a good sign that the engine is receiving sufficient air.

 

 

[Nonimouse]

Going back to what was said earlier, I think your first stratedgy needs to be 'check the simple things (again)'

Don't overcomplicate.  Then if you find nothing odd, look at what is different about your engine

I don't think your gearing is at fault here - if you run the figures through Ashcrofts calcs page, you get 'normal' figures - identical to mine. With a standard turbo max torque is at 1800rpm with max bhp at 3,900rpm. Ideal efficcincy range is at about 2,300rpm - 65mph in 5th, with your set up. Torque doesn't drop off until 3,000rpm - 85mph with your set up.

I'm wondering if this 'Hybrid Turbo' might be the issue. What exactly is this "hybrid turbo"? What has been done to it it? Does it match the boost curve of the standard turbo? Do you have access to a standrad turbo?

[Jocklandjohn]

Aye agree with the simple things procedure, starting with timing check & belt replacement in a week or two, meantime I'll check hoses and connections, lift pump and all those bits that are easily accessible.

Re turbo - hybrid as I understood the explanation is same size/housing as standard but has slightly larger compressor wheel, upgraded bearings generally higher quality materials, polished interior etc but as it retains the standard sized 'snail' all associated piping etc. can be left in place. I'd read about them on here over a decade ago and they were explained as a good way of increasing the flexibility of performance without over stressing the engine too much.

As I'm not interested in thrashing my engine and intend keeping it forever this seemed like a good way to provide some overall improvement for longer runs and carrying the extra weight of camping stuff and family, bikes and dog etc. with the addition of the disco gearing, all of which was discussed with Roland before going ahead. His thoughts matched yours re gearing, as did Ashcrofts when I briefly spoke with them prior to ordering the boxes, so I'd not gone into this blind, rather read up, had seen opinions, got those opinions confirmed! 

I may contact Roland again to see if he can give some more technical details re curve etc which may help going forwards.

27 minutes ago, Nonimouse said:

Going back to what was said earlier, I think your first stratedgy needs to be 'check the simple things (again)'

Don't overcomplicate.  Then if you find nothing odd, look at what is different about your engine

I don't think your gearing is at fault here - if you run the figures through Ashcrofts calcs page, you get 'normal' figures - identical to mine. With a standard turbo max torque is at 1800rpm with max bhp at 3,900rpm. Ideal efficcincy range is at about 2,300rpm - 65mph in 5th, with your set up. Torque doesn't drop off until 3,000rpm - 85mph with your set up.

I'm wondering if this 'Hybrid Turbo' might be the issue. What exactly is this "hybrid turbo"? What has been done to it it? Does it match the boost curve of the standard turbo? Do you have access to a standrad turbo?

 

[Nonimouse]

2 hours ago, Jocklandjohn said:

Aye agree with the simple things procedure, starting with timing check & belt replacement in a week or two, meantime I'll check hoses and connections, lift pump and all those bits that are easily accessible.

Re turbo - hybrid as I understood the explanation is same size/housing as standard but has slightly larger compressor wheel, upgraded bearings generally higher quality materials, polished interior etc but as it retains the standard sized 'snail' all associated piping etc. can be left in place. I'd read about them on here over a decade ago and they were explained as a good way of increasing the flexibility of performance without over stressing the engine too much.

As I'm not interested in thrashing my engine and intend keeping it forever this seemed like a good way to provide some overall improvement for longer runs and carrying the extra weight of camping stuff and family, bikes and dog etc. with the addition of the disco gearing, all of which was discussed with Roland before going ahead. His thoughts matched yours re gearing, as did Ashcrofts when I briefly spoke with them prior to ordering the boxes, so I'd not gone into this blind, rather read up, had seen opinions, got those opinions confirmed! 

I may contact Roland again to see if he can give some more technical details re curve etc which may help going forwards.

 

I've had a few 200tdi's and they remain my favourite engine. I've done all sorts to them over the years. But this has got me thinking.

Your description of the 'Hybrid Turbo' is exactly what I thought it would be. I remember the adverts and my Van Akren tuned 90 (back in the early 90's) had seomthing similar. It will have a very similar torque curve to standard - it's essential ly a better built T2.

If you wern't in the far North, I'd need to pop round to have a look