I
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understand wanting to preserve off-boost response by running a higher static CR, but if you do the maths- you really lose very little power by dropping 0.5:1.
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.
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.it's a surprise when you run the numbers!
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Also- this then allows you to make FAR more power when on boost as you don't have to overly retard ignition- which is a big issue on the 3S engines.
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Other designs of engine can lap it up- but these just don't, and you end up with really high EGTs, a sign of an engine not running to it's full potential.
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But that said- it's all up to you and whoever designs the engine with you, and exactly what you want it to do.
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If you want 500hp to say you have it, but then rarely drive it at that level- then yeah, a higher CR would be fine.
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If you want to drive it at peal boost levels on a sustained basis, then you are risking reliability issues with a higher CR.
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You can build a 3S to run 2 bar of boost at 11:1 CR, but don't expect it to do it all day long.
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.
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.and you'll need to be using a far higher octane fuel than we get in the UK pumps.
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All in my opinion, you'll get different stories from other members on here
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