Original Posted By: Gary Gower
Oscar,A simulated set of curves comparing one engine's performance, even using the sameprop does not give you the standard measurement for horsepower. It only givesyou a set of comparative values. What if the engine that you are using forcomparison has over or understated it's horsepower? Or perhaps the comparisonengine is developing it's stated horsepower at a different rpm? You are onlycomparing one engine against another.There is only one way to measure horsepower and that is on a dyno (water brakeor other) which will measure the foot pounds of torque produced by the engineat different rpm's using a wide open throttle setting. Then one can use the standardformula which is: Horsepower torque times rpm and this result dividedby 5252. This result has to be corrected for standard temperature and pressurethen. Only when this is done, can the horsepower and torque curves be plotted.When I was designing and racing sport cars, many many years ago, I had a dyno inthe shop and tested a fair number of engines. I found that in some cases eventhe manufacturers overstated their outputs (a couple were conservative, probablyto fool the competition). It is only human nature to exaggerate the numbersa little bit if the product is their pride and joy.I am only saying that Wynne's numbers don't add up, or else he would actually havea better rate of climb than he says. A Corvair is a good engine, no questionabout that, it simply needs to be presented to the users in a thoughtful andwell documented manner.John ________________________________________________________________________________Date: Sun, 8 Dec 2002 21:47:33 -0800 (PST)