Joe Beyer wrote: > No, Stainless steel valves are worse. They're soft and although they're > one > piece, as opposed to welded, they stretch and are more expensive. I threw > away a set of them due to compression loss after just a few hours of use.
There are good stainless valves and bad stainless valves. You must have bought some bad ones, because the good ones are an improvment over stock. I bought a set of el cheapos once my self, and the rockers chewed the ends up in no time. Good ones don't do that. As a data point, William Wynne recommends stainless exhaust valves in CorvAircraft engines, and it's not because they are inferior to stock. > Having flown behing behing a VW for 125 hrs. I've found that VW's have an > easier life in an airplane than in a car. They run at pretty much one > speed > all the time and at one tempature and are not used as an inertia brake, > ie. > down shifting. .... I usually cruse at 2500 to 2650 in my KR which > is lower that in my VW bug. Just because your airplane turns fewer rpm than your bug, doesn't mean the airplane's not working a lot harder. The airplane is at almost full throttle, and your bug is rarely full throttle for very long, or you'd be going 90 mph or so. 2600 rpm in a bug is 52 mph, and I'll bet the throttle's not 30% of the way open. VW busses ARE run full throttle much of the time, but they have a lot more problems too. I used to be the engine mechanic at the VW dealership in Las Vegas (was Prestige Motorcars, now Cutter, I think), and in the summer time they were lined up in front of the shop on Monday mornings, victims of the steep hills between California and Vegas. I could argue all day about this, but there's no doubt that aircraft use demands far more from an engine than automotive use. Mark Langford, Huntsville, Alabama see KR2S project N56ML at http://home.hiwaay.net/~langford email to N56ML "at" hiwaay.net
