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craggsy

Questions on compression ratio (CR)

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Right i'm thinking of lowering the CR on my engine when I, well Dave does chains and pops a P&P head on. I know that pistons would be safest and best way of doing it but thats plenty $$$$ that I dont have. So using spacer gaskets will be the way for me. Doing this as I wanna be getting engine running spot on before I do any major mods ie FI.

So tell me what would be best thing to do?

Ta

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Not silly amounts of power as I dont know if im going turbo or supercharger yet. But aiming for at least 300bhp.

I have a fair bit to spend but some of it is going towards getting chains done and head work.

Im thinking long term but without spending silly amounts on it as its a daily and money isnt easy to come by.

I know if i had money id just get some low comp pistons but that isnt an option at the moment, just looking to get the basic engine almost bullet proof for now and set up for adding FI later

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im liking this thread as am to trying to get engine running spot on before fi. craggsy cant you use the 2 layered headgasket with steel in between. This seems to be what people are doing on the turbo'd vr6s

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im currently getting headgasket, inlet manifold gasket, valve stem seals etc replaced with new bolts all round as headgasket is leaking and radiator has got a hole in it.

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We have done 5 or 6 MK3 R32 conversions at work in the past month and they all made between 280 and 290 hp, the economy is still reasonable also especially for a daily driver! I really do think you should consider going to the 3.2 its just a much better engine all round.

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I hate to say it but 8.0:1 is just too low' date=' 8.7:1 is as low as you want to go really.

[/quote']

cool cheers alex i have been thinking this since i done it ... mite just use one layered gasket and split it ...

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If you want to make a 12v engine bulletproof you need to spend a fair bit of money. I spent thousands on mine forged rods, pistons etc and the head gasket still let go twice at 25+psi.

Have a look to see what you can buy a 3.2 engine for?

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when i rang stealth racing up a few weeks ago they qouted around £3000 pound for a stage 1 supercharger setup that was drive in leave the car and drive out job. Thinking of getting it done later this year/ early next year. wats the diffrence in price between turbo and supercharged as still havent made my mind up as which route i want

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if your going turbo route try giving jkm a call seem to no there stuff and radostorm got his corrado done in there. in fact it was in there only yesterday

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We have done 5 or 6 MK3 R32 conversions at work in the past month and they all made between 280 and 290 hp' date=' the economy is still reasonable also especially for a daily driver! I really do think you should consider going to the 3.2 its just a much better engine all round.

[/quote']

what mods have you done to get them figures from them?

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But if I stuck with the 12v would dropping CR to say 9:1 be ok for NA for the time being?

I dont think i would be aiming at the sort of boost that your running tho Alex......modest boost would see 300bhp as proved on quite a few cars and is useable

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We have done 5 or 6 MK3 R32 conversions at work in the past month and they all made between 280 and 290 hp' date=' the economy is still reasonable also especially for a daily driver! I really do think you should consider going to the 3.2 its just a much better engine all round.

[/quote']

Do you work for storm now alex?

Eat this i think them figures are on standalone + exhaust manni

craggsy think you've answered your own question lol :) headspacers and aprs work for 100s of fi vrs around the 300 mark.... 8.0:1 is only for really HIGH boost levels

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