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Old 04-28-2012, 12:16 AM   #25 (permalink)
3-Wheeler
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Quote:
Originally Posted by smokey442 View Post
BMW published a paper in this subject including optimum bore and stroke. The v8 wins out for reasons of lower heat rejection rate and accessory losses (oil pump and waterpump)
Consider the quote "The V8 wins out for lower heat rejection rate..." ...

This goes contrary to typical thermodynamics text books.

I also have direct experience with $15,000 pressure decay testers that say that heat rejection would go up (be quicker) with more cylinders (larger surface area to the cooling air).

It is well proven that for higher fuel economy, less cylinders equals more. You want to maintain the heat in the cylinder for moving the piston down, not heat the air around the outside of the cylinder, and waste it to the air flow.

Jim.
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