AeroVee performance issues

[mike.smith]

Mike

Have you tried taking off your air cleaner? When I went on K&N website and checked their formula it showed that the standard air cleaner that comes with the AeroVee is not large enough to produce enough air to create 80 hp. I modified my air cleaner. At WOT I am turning 3550 RPM and showing 150 mph. Just a thought .

I have the over sized K&N filter. I had to make a blister on the bottom of the cowl to get it to fit. I've run the engine with the filter off and didn't see any appreciable difference.

[mike.smith]

Going to and from OSH this year, and putting about 20 hours on the plane, I was at about 75% full throttle, at 3,160 rpm, leaned back, doing 103 kts indicated, 106 kts TAS, burning an average of 4.5 gph. With the enlarged cowl exit my temps were so far in the green it was scary :-) Even on a hot day, high humidity, climbing out at full throttle, my hot (#1) cylinder didn't get over 350 F, and EGT never got over 1350. In cruise that CHT was normally in the 315-320 range, with EGTs around 1290. The #2 and #4 cylinders are regularly in the 280 F range, with 1220 EGTs. Opening up the exit air made a HUGE improvement in temps. Like nearly a 100 deg F difference in both EGT and CHT! I'll quantify the area and post it when I get a chance.

[gammaxy]

At WOT I am turning 3550 RPM and showing 150 mph. Just a thought .

That's some serious RPMs compared to what I see with my Prince 54x46. Are you using the Sensenich 54x44? What rpm do you get on climbout? I'm considering experimenting with a different propeller.

Going to and from OSH this year, and putting about 20 hours on the plane

Sounds like things are working good for you now. I'll be interested to hear more about your results from enlarging the exit. So far, my exit seems sufficient unless its a hot day and I'm operating near gross weight, but I can always keep the temperatures within limits by reducing the climb angle.

[jwd3ca]

I came to the same conclusion several years ago with my 3300/AeroCarb, and went with a K&N RU-0660. I'm now looking for an air cleaner for an AeroVee/AeroInjector and would assume that the one that Sonex sells is being used by dozens of AeroVees with no issues. I just have to wonder why Sonex, after all these years, continue to recommend and sell an air filter that was incapable of providing sufficient air for the engine it was sold to fit? That just seems implausible to me...