Pietenpol-List: how stressed is the Corvair on an Air Camper?
Posted: Sun May 10, 2009 9:13 pm
Original Posted By: "Dick N."
Raymond wrote:>the only thing that makes me wonder about trying to get full rated horsepower and more>from a car engine is -I doubt they're built for continuous duty at the figures unless it's an> industrial engine that pulls the load in more or less full time service I would> expect there to be problems getting rid of the heat at the least.but here I> am getting ready to fly behind a Corvair engine that was never designed as far> as I know for continuous full power application. but I'd hope to be able to> throttle it back some when at altitude.if it is propped right>From William Wynne's website=2C http://www.flycorvair.com:> In the Corvair automobile=2C the engine produced 180 horsepower in the turbo-charged form. All 1964-69 model engines utilize the same crankshaft=2C rods=2C pistons=2C cases=2C etc. By flat rating the engine for 90hp continuous=2C the engine is only stressed to 50% of its rating in the automobile. No other auto engine conversion can make this claim. In the automobile=2C the engine redlines at 5=2C500 rpm. My aircraft conversion produces 75% power at half this rpm. These two facts form the cornerstone of the Corvair engine=92s reliability as an aircraft power plant.> The Corvair engine turns more than 3=2C000rpm at 60mph in the automobile. They can run for hours at a time over 4=2C500rpm. Asking the engine to produce 75% power=2C the brake mean effective pressure (BMEP) is lower at 2=2C800rpm than at 2=2C000rpm.Oscar ZunigaAir Camper NX41CCSan Antonio=2C TXmailto: taildrags(at)hotmail.comwebsite at http://www.flysquirrel.net________________________________________________________________________________
Raymond wrote:>the only thing that makes me wonder about trying to get full rated horsepower and more>from a car engine is -I doubt they're built for continuous duty at the figures unless it's an> industrial engine that pulls the load in more or less full time service I would> expect there to be problems getting rid of the heat at the least.but here I> am getting ready to fly behind a Corvair engine that was never designed as far> as I know for continuous full power application. but I'd hope to be able to> throttle it back some when at altitude.if it is propped right>From William Wynne's website=2C http://www.flycorvair.com:> In the Corvair automobile=2C the engine produced 180 horsepower in the turbo-charged form. All 1964-69 model engines utilize the same crankshaft=2C rods=2C pistons=2C cases=2C etc. By flat rating the engine for 90hp continuous=2C the engine is only stressed to 50% of its rating in the automobile. No other auto engine conversion can make this claim. In the automobile=2C the engine redlines at 5=2C500 rpm. My aircraft conversion produces 75% power at half this rpm. These two facts form the cornerstone of the Corvair engine=92s reliability as an aircraft power plant.> The Corvair engine turns more than 3=2C000rpm at 60mph in the automobile. They can run for hours at a time over 4=2C500rpm. Asking the engine to produce 75% power=2C the brake mean effective pressure (BMEP) is lower at 2=2C800rpm than at 2=2C000rpm.Oscar ZunigaAir Camper NX41CCSan Antonio=2C TXmailto: taildrags(at)hotmail.comwebsite at http://www.flysquirrel.net________________________________________________________________________________