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eeyoreish

HC Engine in a non-HC Car

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What are the implications of putting an HC engine into an S3 Turbo that originally came with a non-HC engine? Will all the ancillaries  from the original engine fit straight on or are there some differences I should worry about? Any difference in things like gearbox, clutch, turbo etc?

 

Edited by eeyoreish

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There's loads of detail differences  (off the top of my head - wastegate, carburettors, inlet manifold, larger inlet ports, air pressure piping).   However, I can't think of any 'show stoppers' that would stop you using all LC ancilliaries with an HC engine  (other than you may end up without the performance benefit of the HC!).   I also believe the items you list above are all the same.

I use an HC head mated to an LC inlet manifold, opened out to match the HC ports, works very nicely.

 

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Mine has an HC engine (it is an S3 non turbo though). It required a fair few changes to cooling pipework I know and also some mucking around with the clutch slave / clutch fork. (I think the later gear box has it mounted in a different place to the earlier cars). But all was doable with other esprit parts though.

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27 minutes ago, skiing said:

Mine has an HC engine (it is an S3 non turbo though). It required a fair few changes to cooling pipework I know and also some mucking around with the clutch slave / clutch fork. (I think the later gear box has it mounted in a different place to the earlier cars). But all was doable with other esprit parts though.

So a different clutch fork and slave or just mounted differently? Are you running the original carbs etc?

1 hour ago, 910Esprit said:

There's loads of detail differences  (off the top of my head - wastegate, carburettors, inlet manifold, larger inlet ports, air pressure piping).   However, I can't think of any 'show stoppers' that would stop you using all LC ancilliaries with an HC engine  (other than you may end up without the performance benefit of the HC!).   I also believe the items you list above are all the same.

I use an HC head mated to an LC inlet manifold, opened out to match the HC ports, works very nicely.

 

OK, so at least some of the big stuff is the same! What's the difference in the carbs? Sounds like the originals would work OK though? 

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Clutch slave no difference on a Turbo LC/HC both mounted to the RHS.   

That's a good point on the pipework.   The LC has a 'fat' waterpipe leaving the front of the head.  The HC has a small pipe leaving the front of the head (the stubs are interchangeable, so I swapped the stubs and fitted the LC stub to the HC head 

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Mine has the same carbs as before but had to be re-jetted for difference in power (I also have a lotusbits exhaust on it). I think I ended up with a (metal) coolant pipe from an S4 which goes over the top of the cambelt.

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Hmm... some challenges to overcome then but nothing major. Not sure I'll have access to the old LC engine but sounds like that would be a useful bonus for parts interchanging!

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