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How Terrible Will A Compression Ratio Of 9.2 Be Short Term?


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#1 dyshipfakta

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Posted 13 January 2020 - 08:58 AM

As above going to put a 12g295 on my 998 my calculations give me roughly 9.2 compression ratio. Will this be usable? My plan is a turbo conversion down the line but would like the option to do it in stages.

#2 DomCr250

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Posted 13 January 2020 - 10:28 AM

Standard 12G295 on dished 998 low compression pistons works fine - it will rev a little better but you wont get the power gains that a slightly higher ratio would give you.

 

So you might make a handful extra HP.



#3 unburntfuelinthemorning

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Posted 13 January 2020 - 02:45 PM

The compression ratio on non A+ non Cooper 998cc engines was only 8.3:1



#4 dyshipfakta

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Posted 13 January 2020 - 05:20 PM

That is what I was thinking to be honest I have just never driven one. Only high compression 998s. I’ll plonk it on she how she goes then. Thanks

#5 absx2

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Posted 13 January 2020 - 07:53 PM

It will be fine and you can use cheap super market fuel with no running issues.

I think the 998 cooper CR was 9:1 or maybe 9.4:1 so you`re pretty much on the money.






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