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Wayne 962 Wayne 962 is offline
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Originally posted by snowman
That said, I just love the smell of race gas and the sound of 12.5:1 Porsche cylinders firing.
Finally, snowman is coming around!

Seriously - the issue of detonation is important with respect to your question. However, with twin-plugging, it becomes less of an issue because you have dual ignition on both sides of the piston. Single plug would be a big problem, but in this case, you're firing both sides of the combustion chamber.

Your compression ratio numbers seem reasonable for what you are looking to do. Important benchmark - the 964 engines are rated at about 10.5 - 11:1 ratio (there's some debate over what they really are). They have twin-plugs, but they also do benefit from a knock sensor, as snowman eluded to.

Wayne R. Dempsey, Founder, Pelican Parts Inc., and Author of:
101 Projects for Your BMW 3-Series101 Projects for Your Porsche 911How to Rebuild & Modify Porsche 911 Engines101 Projects for Your Porsche Boxster & Cayman101 Projects for Your Porsche 996 / 997 • SPEED READ: Porsche 911 (October 2018)

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Old 01-11-2005, 10:31 PM
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