Project Gemini - Naturally Aspriated version of 200TDi?

[western]

doubt there would be any change due to the vehicles weight/size & there would be a lack of bhp/torque,

[Rightfoot]

For my sins I was working in Land Rover (in purchasing) when the Discovery was launched - I cant remember much from back then but I do know for a fact that both the inlet and exhaust valves were different for the non-turbo Tdi. Dont ask me what the differences were - from memory the 200Tdi valves were ERR1156 and ERR1157, so the non turbo ones were probably ERR1154/55 (or possibly ERR1158/59). The supplier was TRW who I think are still in the same place.

At a guess it would be either material or heat treatment, but its entirely possible that they were a different shape.

I realise this doesn't add much to the whole debate, buts it is one more (slightly anorak like) statistic.

A quick comment on the tooling for the cranks as well - at some point in its life it would be refurbished / replaced, so the old BL logo could have disappeared, equally well if the supplier had changed then new tooling could have been made. For castings tooling has a relatively long life (i.e. years) for forgings its much shorter - so a change in position of logo etc. really doesn't mean anything.

[Daan]

So, in a 110 say, which would be more economical? a 200 tdi or a 200di

The TDI, without a doubt, provided you use the same amount of power. This is why I believe the whole DI idea is a waste of time and effort myself, but that is just my opinion.

Daan

[Tanuki]

For my sins I was working in Land Rover (in purchasing) when the Discovery was launched - I cant remember much from back then but I do know for a fact that both the inlet and exhaust valves were different for the non-turbo Tdi. Dont ask me what the differences were - from memory the 200Tdi valves were ERR1156 and ERR1157, so the non turbo ones were probably ERR1154/55 (or possibly ERR1158/59). The supplier was TRW who I think are still in the same place.

Just because a part-number may have changed doesn't mean the specification of the part is different: I've come across several instances where a supplier has changed *their* part-number because of a new contract being established, which is then reflected in a different part-number being issued by the end-user organisation. The parts themselves remaining entirely the same throughout !

[ejparrott]

Just to throw a spanner in the works with my 2p.

My 88 has been running 200TDi disco for about 5 years now, coupled to a series gearbox. I'm running a series rad, with no expansion tank, I've got no intercooler, and no fan, and return 30mpg with ease. My oil cooler is currently a Vauxhall Callibra gearbox oil cooler, but about to change to a proper 2" square seven row cooler. I'm a sympathetic driver, my wife however is not, far from it. Despite the abuse she gives it, I've not thrown a 'box, or a clutch, or a half shaft, or a diff. Well, I did throw a diff the other week but it looked as though it had cracked quite some time ago and was syeadily working through. What I've got, is about the simplest conversion you can do.

Why not just rebuild a 12J NA? They're a doddle to work on, and when it good order, freshly rebuilt, I've found they do perform very well. And they're an NA engine from the start!

I once blew my inlet hose off, so was effectivly running as an NA. It was gutless. I thought I had a blocked fuel filter it was so bad. I coudln't get it over 40mph, and that was almost impossible to reach.

[Aragorn]

Bear in mind that a 200"Di" wont be quite as bad as a 200TDi with a blown boost hose, as the 200"Di" wont be trying to expel all its air thru a tiny volute in the turbine housing!

That said, i'd absolutely be leaving the turbo fitted. By all means back off the boost compensator or even knock the base boost pressure back by adjusting or changing the actuator if your scared of blowing the transmission up, but the turbo really helps things along, and will improve MPG by allowing more complete combustion.

[Dave64]

Hi All,

Know this is an old post, but I only came onto it by pure chance.

I too have often wondered just what the results would be as per twodoorgaz's project. I too have a project very similar to that he's doing where I neither need nor require either the Turbocharger or the intercooler.

My own thoughts are/were that the main points of Gaz's thrust were being treated just  a little disdainfully.

I'm with him in many ways, he posted a topic asking for input, which was readily responded to but to be fair, as an outsider some of the comments were a little offhand. He openly stated that this is what he wanted to achieve, he was prepared to go about it in such a way and be damned with the consequences! Can't ask for anything straighter than that!

Quite a few of responses were from people whom i respect on this forum, have gleaned some good info myself to suit my own particular project.

I did notice that the topic seemed to have just dispersed into thin air with no apparent confirmation, after about three pages. Does this mean that consensus couldn't be reached? I for one would like to know if twodoor gaz and his "Project Gemini" ever came to fruition and just how successful it was, especially relating to derating the actual engine.

I'm one of these blokes who like to not only think outside the box, but also enjoy seeing others doing the same. When a lot younger I was one of those who would race out and buy the latest "hottest" gear available to bolt onto my Yank Iron. Learnt after a while that sometimes it is not ONLY about squeezing the maximum HP out of a known volume, nowadays it is about a thing called reliability and longevity. Unless I'm mistaken or reading it wrong, this was the main gist of twodoorgaz's letter in the first place. He openly stated, "it's my money, my time, it's a lifetime project and I'm gonna give it a shot"!. Well, all I can do is agree with him and say more power to your arm! 

Like a lot of forums, sometimes people get sidetracked from the original topic, that's not to say it's not entertaining, but often the main thrust of the query gets bogged down. So, again I ask his question. The basic guts of it seems to be, turf the turbo, the intercooler, reset the pump back to an N/A setting and let the HP/torque figures fall where they may. AND, nobody had came up with expected figures. Or I missed that as well?

Cheers to All Dave64

[Snagger]

I still haven’t seen any figures, but because of the better atomisation for the fuel, you should be able to get better than 12 J performance and markedly better economy.  We all know the 200Tdi is pretty robust, so with less thermal and compressive stress, it should run a very long life.  I remember meeting a guy off the old LRNet forum who went by the tag Jayhoe, and he was really pleased with his 200Di in his 88”.  He said it was peppy enough, and didn’t need more than the original SIII rad, no oil cooler and obviously no intercooler.  Nice and simple.

At the end of the day, do what you’re happy with, and if you keep the turbo and associated bits, plus oil lines and ideally the donor rad, then you can always add those later if dissatisfied with the normally aspirated performance.

[Mo Murphy]

Have pmed him to ask him how he got on directly ?

Just a thought

Mo

[Dave64]

Thanks for the replies, Men.will shoot twodoorgaz a P/M as suggested.

Dave64

[Nonimouse]

Oddly enough, I was just looking into the other Gemini engine. The Petrol in line 4....

[western]

That version never came to production. 

[Nonimouse]

1 hour ago, western said:

That version never came to production. 

I know, but I was pondering building one

[western]

would be a interesting project, don't know what cylinder head you would use to get spark plug holes in the right places.

[Nonimouse]

As far as I can tell, the injector holes are in the right places for a spark plug, because it's a DI. Part of the original design

[Sheffield]

How would you reduce the compression ratio to suit? Have a steel plate cut to go between the head and the block? With electronic ignition systems taking a signal from some where sparks would not be too difficult, but how would you inject and control the fuel? Perhaps use some thing from the earlier 2.5 petrol engine?. It would be an interesting project, which might provide an engine with the capability for a very long life.

[Bowie69]

Different pistons for sure,the diesel ones have all sorts of funny shapes going on.

[Gazzar]

How different would that be from the 17H engine? Alloy head?

Chain or belt?

 

[Daan]

I really cannot see the point of downgrading an engine; turbo charge and intercooling is pure gain on any diesel engine with no disadvantages to speak of. If it is too much power to take for a series gearbox, just reduce the max fuel adjuster a bit to reduce fuel delivery. You will still have all the advantages of the turbo and intercooler, and you will never see full power. The best fuel consumption and therefore the best solution by a long way IMHO.

[Gazzar]

On 7/25/2020 at 12:32 PM, Daan said:

I really cannot see the point of downgrading an engine; turbo charge and intercooling is pure gain on any diesel engine with no disadvantages to speak of. If it is too much power to take for a series gearbox, just reduce the max fuel adjuster a bit to reduce fuel delivery. You will still have all the advantages of the turbo and intercooler, and you will never see full power. The best fuel consumption and therefore the best solution by a long way IMHO.

Technically true, but it does complicate the installation, for those who fear their fabrication skills are lacking, this is an issue.

[Snagger]

On 7/25/2020 at 3:32 PM, Daan said:

I really cannot see the point of downgrading an engine; turbo charge and intercooling is pure gain on any diesel engine with no disadvantages to speak of. If it is too much power to take for a series gearbox, just reduce the max fuel adjuster a bit to reduce fuel delivery. You will still have all the advantages of the turbo and intercooler, and you will never see full power. The best fuel consumption and therefore the best solution by a long way IMHO.

I agree, but these guys were worried about the gear box and trying to do an easy conversion without chopping the engine bay about.  I wouldn’t do it, but if it suits them and they’re happy, then good for them.