04-24-2010, 10:20 PM
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Senior Club Cobra Member
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Join Date: Feb 2007
Cobra Make, Engine: KMP 539, a Ton of Aluminum
Posts: 9,591
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Not Ranked
Rebuttal of the "Less Stroke/Cubes=Rev Faster" Argument
Is it? I remember reading that there some who build a 445 or a 468 for the 4.125 stroke. Well, this response to a thread was posted today by noted and published FE guru Jay Brown over on the FE Forum:
"I personally don't believe the BS about big cubic inches don't rev. My 585" SOHC, with a 4.6" stroke and 4.5" bore, regularly bangs off the rev limiter at 7500 on the track. My shift light is set at 6700, but last year I was hitting the rev limiter in first before I could shift nearly every time, and sometimes in second too. The engine revs faster than any smaller engine I've ever had.
A big stroke will cause you more frictional torque and power losses than a small stroke. Given the same number of cubic inches, a smaller stroke bigger bore engine will make more power, especially at the top end. But if not class limited to some cubic inch displacement, I will take a 482" 427 stroker over a standard 427" engine every time. The extra cubic inches translate to lots more torque and horsepower. Look at NHRA pro-stock vs. the larger cube IHRA pro-stock cars. The IHRA cars are faster by 3-4 tenths, and down in the six second range that's a lot.
It sounds like you have a street car, so maybe my little diatribe doesn't apply to you. But especially with a street car, cubic inches are king. Put in the 4.375" stroke crank, and have fun."
Here's the entire thread: http://www.network54.com/Forum/74182...k%2C+now+what-
Thought provoking?
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