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Here is an example of the dated design of main stream private sector aero engines. About 1997 ish I got involved with Magnum Engines on an upgrade of an IO 540. When I checked the cam on my computerized checker I could hardly believe that this was what they were using for however many years the engine has been in existance. Remember we have an engine that is supposed to turn no more than 2700 rpm. Why in the world do they install a cam that is about 300 degrees duration at lash. Also the dynamics were dreadfull. I can tell you with absolute certainty I can file a better cam than that. Any way we had Harvey designs some new profiles that were about 30 degees shorter and with top notch dynamics. I can't remember for sure but it think the end result was abolut a 20 hp at 2500 rpm (about 40 lbs-ft). Along with this the fuel consumption was less! A check with Magnum Engines (in Ontario Ca. last time I heared from them) will get you aero buffs all the details you need.
As for auto powered kit planes Bruce Crower built, I believe, an RV4 with a 430 inch all aluminum SB Chevy in it. I heard it had about 375 horses but, if you need a number for sure I'll bet the guys at Crower will tell all.
DV
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