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In a message dated 2/12/03 8:28:56 PM Eastern Standard Time, [EMAIL PROTECTED] writes: > My question is what is the horsepower of this engine? There are many answers to that question. First of all, it is still a C85 and legally must be operated according to the limitations (red line) of a C85. Due to the physics of fixed pitch props, it won't produce more cruise power than an unmodified engine at the same RPM with the same prop in the same airframe. It will produce more power in climb, but since climb power is considerably below red line, it'll likely still be less than 85 hp. > I have been told there > is a difference in HP due to the difference in weight of the pistons and > compression, and was told to use only 89 octane or 100LL. Compression and displacement are higher. Same as a C90/O200. 80 avgas or 87 mogas is fine. If the STC says otherwise, then that's what you must follow. The holders of the > STC say no horsepower was submitted to the FAA when it was approved and they > did not require one. > I have been told unofficially that if the engine is run > as an 0200 it produces 103hp, if run as an 85(which is required) it develops > 93 to 95 HP? Has this combination ever been horsepower tested to show the > real HP? I understand that Don's Dream Machines, one of the STC holders, has done testing and come up with similar numbers. Again, though, what it's capable of and what it'll do in a legal installation, are two different things. Remember, your red line is still 2575, and your prop is designed for an 85 hp engine. To get the most out of it legally, repitch your prop for red line at full throttle level cruise at (near) sea level. Sort of like the new Cessna 172 vs the 172 SP. One is 160 hp and the other is 180 hp. Same engine, diffferent red line and prop. You cannot simply operate the 172 as an SP because of the red line restriction, and because the prop won't cut the mustard. YMMV, John ========================================================================== ==== To leave this forum go to: http://ercoupers.com/lists.htm Search the archives on http://escribe.com/aviation/coupers-tech/
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