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Old 06-10-2012, 06:51 PM   #18 (permalink)
metromizer
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Quote:
Originally Posted by ERTW View Post
Yamaha 5 valve tech will not knock - 93 octane with 13.5:1 cr! The corvette LT5 was said to run fine on 87 octane with 11:1 cr.
A lot of recent engineering has gone into homogenous charge, better mixing of the fuel and air within the combustion chamber. That, coupled with better 'active' fuel/spark controls I think is what allow today's engines to use higher compression ratios with relatively low octane fuels.
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