> > > >Greg how about a status report on your airplane?? How is it going??
> > > >I am dying of curiosity about what kind of exhaust temps you are
seeing
> > > >with your turbo charger.
>
> What kind of exhaust temperatures has this group experienced between turbo
> and non-turbocharged Mazda 13B's?
>
> Thanks,
>
> Rob Weinstock
People have seen up to 1800 degrees F non-turbo. Lot depends on how you lean
it. Tracy Crook has leaned his engine to 100 degrees lean of peak or more and
seen the temps drop to 1500 degrees or so as I recall. Unlike a piston
engine
it is safe to do this as there are no valves to burn in case you
mess up and run at peak EGT for awhile. I run my O-470 50 degrees
rich of peak just to be on the safe side.
I think stock turbos are limited to 1650 F or so. With an Inconel
wheel I think the number is around 1750 or 1800 degrees F.
Paul Lamar
A problem with the 0470 is distribution and low compression. One end is
allways running leaner than the other. If you have 6 EGT probes, you can lean
the hottest cylinder lean of peak.
The leanest cylinder is running lean enough to get rough and another cylinder
is still just rich of peak ( where the highest heat and stress is generated).
The non turbocharged rotary, is insensitive to mixtures around peak EGT. The
possibility of apex seal damage, from operating for extended periods at peak
is real. The engine will run just fine, and seem to pull hard both sides of
ideal mixture. On the race car we have trouble keeping it rich enough at full
tilt (8,000 to 9,400 RPMs). Here is a situation where injection would cure
the problem. Lean of peak is cooler, less stress
on the engine, better fuel mileage, less crap buildup in the engine and clean
oil.
The engine man wants us at 1575 EGT in the mid range. The best power is just
rich of peak, and we pass through that just before the shift.
Lynn E Hanover
The AirCraft Rotary Engine NewsLetter. Powered by Linux.
ACRE NL web site.
http://home.earthlink.net/~rotaryeng/ http://www.linux.org