I installed a Tee fitting on the oil outlet of the filter, so I could measure the oil temp after the coolers, as it enters the engine.   Best I can tell, the coolers do nothing, or at least nothing much.  I took the plane for a short flight, and the oil temp hit 240 by the time I got to 2000 ft.  This is at a much higher power than before, so it might be cooler than what I would have been measuring in the pan, but it’s still completely unacceptable. 

I found that 12 degrees of pitch on the prop is probably not quite enough.  I ran 6300 rpm on climb at about 110 mph.  The plane still doesn’t seem like it’s climbing all that well, but I think that’s deceiving.  It sure pins you back in the seat on departure.  Unfortunately, I didn’t get any VSI reading from the anywhere map software.  It just sort of wallowed around at completely bogus numbers.  

The plane certainly has the power to bring people out of their hangers.  Nothing like 6300 rpm, and 3 psi of boost on an open turbo during departure :-)  People on the ground said it sounded like it was making 500 HP, and I told them it was closer to 210 HP if I had to guess.   Unfortunately, the flight was followed by perhaps the worst landing of my life.  I’m going to start wheel landing this thing, because I just can’t quit doing a perfect full stall landing 3 ft off the ground.  There’s a fine line between landing, and accident.

Not sure what to do now, but clearly, the Howe oil/water heat exchangers have flown their last flight.   Here are the options as I see them:

1- Since I sized the current radiator to cool the water, and oil, and I know that it has excess capacity, I could add a real oil/water heat exchanger.  The downside is that it would be another heavy item to worsen my forward CG, not to mention the fact that it's expensive and not guaranteed to work.  It also means I have to keep my big radiator, which is the main reason the cowl is so ugly.  The good part would be that it could be put inside the big ugly cowl with relatively little difficulty, and I could press on with flying the plane. 

2- I could add an oil/air cooler, and keep my current oversize radiator and cowl.  I have a 2nd gen cooler on hand, and could put it in the right cheek, or perhaps above, or below the current radiator.  Below would be better, but I can't get the hoses to it, so it would probably have to be above.  The negative of course is keeping the oversize radiator, for no good reason.  The only positive is that I could continue to fly the plane for now, without major downtime.  

3- Finally, I could add an air/oil cooler, and replace the current radiator with something smaller.  Of course doing this would mean re-doing the bottom cowl, which would also make me want to re-do the top cowl, which means a new intake to get rid of the bump, etc.  This option would almost require me to pull the wings off, and move the plane back home.  That isn't an appealing idea at the moment.  

Has anyone seen an air/oil cooler that has a large frontal area, and is fairly thin?  I'd be interested in something that I could put in front of the radiator, sort of like an air conditioning condenser coil on a car.  Hmmmm :-)

Cheers,

Rusty (not sure when I'll fly again)