998 cylinder heads, suitable camshafts and compression ratio

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dhenry
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Re: 998 cylinder heads, suitable camshafts and compression r

Post by dhenry »

That sounds like a cracking set up and probably just about the same as what I will end up with. My aim is to crack 100bhp/tonne. Flywheel that is. Will definitely go hotter than 266 I think. 276 or 286 for sure. Depends what I find. And lightened flywheel for sure.

Smiffy. Just to get this straight. You say with half inch clearance there is plenty of room for skimming. So 120thou for 9:1 CR should theoretically be totally fine?

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Smiffy
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Re: 998 cylinder heads, suitable camshafts and compression r

Post by Smiffy »

dhenry wrote:Smiffy. Just to get this straight. You say with half inch clearance there is plenty of room for skimming. So 120thou for 9:1 CR should theoretically be totally fine?
On the three heads I've measured you can take off enough, that the thickness of the deck would come into question. Before you get anywhere near the oil drilling.
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dhenry
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Re: 998 cylinder heads, suitable camshafts and compression r

Post by dhenry »

Ok, I see. Well if the oil way is fine and the deck gets too thin what are the potential problems one might face?

Also, when skimming a head I would assume you would need to shorten your pushrods also?
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mk1rally
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Re: 998 cylinder heads, suitable camshafts and compression r

Post by mk1rally »

You may be able to shim the rockers to make up the difference.
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