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I'm considering changing my bottom-mounted oil cooler to the top-mounted cooler for my AV 2.1.

1) For anyone that has made the switch, did you note any changes with oil temps or CHTs?

2) The instructions don't say anything about modifying the baffles, but I did notice the Turbo installation manual shows the rear baffle being modified to exit the cooling air directly to the engine compartment. So just wondering if that needs to be or should be done to keep the temps down within the baffles?

3) I laid the top mounted cooler loosely in place on top of my engine and then laid on the top cowl (I have a horizontal split). There was interference with the front flange of the oil cooler, which is about 1/8" high. It looks like if I cut off that flange it might just fit. Anyone else have this issue and solved it?

Thanks,

I have the top mounted for my turbo and also the horizontal split cowl. I can tell you that my cooler definitely needed trimming to fit. I trimmed what I could but it still rubs and is leaving small marks on my cowl.

I heard they are making a new mounting bracket that will locate the cooler back a small amount to resolve the issue. I am patiently waiting and then will replace my upper cowl.

One reason for making the oil cooler change is in case I do look to make the Turbo conversion. :-) Liking yours?

I have wondered what happens with the lines that go from the oil pump to the bottom mount cooler when when you fit a top mount cooler. Do you need to change the oil pump?

phenry wrote:I have wondered what happens with the lines that go from the oil pump to the bottom mount cooler when when you fit a top mount cooler. Do you need to change the oil pump?

From the Aerovee 2.1 Assembly & Installation Manual page 55:

Run a loop of -06 braided hose from the inlet of the existing oil pump to the outlet port.
or:
Remove the oil pump and replace it with a Standard Oil Pump, AeroConversion part number ACV-P01-56

I changed to the top cooler before the turbo upgrade. I ran a loop of AN-6 braided hose between the inlet and outlet ports on the oil cooler. When I did the upgrade the new oil pump eliminated the hose. The hose loop worked just fine for the several hours I ran with the top cooler. I made a tunnel into the rear baffle since i didn't want to buy more cowl seal and upset a well sealed top at the rear baffle. The temps were mostly the same and often a little cooler (oil temps) after the change, less than noticeable for the most part. I have the vertically split cowl so I had to remove the front flange to let the cowl fit and also had to file a small grove for the hinge. The instructions show that the whole top layer of cooling fins and top plate have no oil in them and can safely be removed. The mod is pretty easy and makes one less thing to remove at every oil change. After blowing a bottom cooler, I wish this was an option when I did the first build on the engine.

Having only flown a non-turbo during my transition training, I can say that I would fly the turbo if you can afford the investment. I am very happy with my performance, it's very different from a NA Sonex. Climbs hard and cruises fast.