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Interesting Rusty. My take on the oil pressure is that the restriction of the oil cooler (evap core) is not a big factor. Who cares whether the pressure is dropped by the cooler or the oil pressure regulator? (until it drops it below regulator spec of course)

Agreed. I was just getting paranoid about having another failure of the oil cooler, and felt compelled to actually prove what the pressure was. I feel better now.

Aren't these types of oil pumps considered positive displacement pumps? In other words, they displace a certain volume with every turn. If that's the case, it would seem that a higher volume pump would be a good thing for cooling. The extra volume would get bypassed at the regulator, and would get sucked right back out of the pan and sent back to the oil cooler. Just seems like this would be a way to get more cooling out of a given cooler size. It might not quite work that way in reality, but I'm just trying to think of anything that could help oil temps. Not likely I'll be changing oil pumps.

What really concerns me is the poor oil cooling you are getting. I plan to use an evap core for the 20B and on my mental scratch pad, it should be better than the Mazda oil cooler in aircraft applications. Wish I knew what the air pressure in front & back of your cooler is. Pressure recovery is real important with evap cores.

Don't get too concerned yet. It was working great before I started making "C" power, despite the fact that the installation is far from ideal. The oil cooler scoop looks nice, but doesn't have the best pressure recovery shape to it. The air has to turn about 60 degrees to get into the core, then about 80 degrees to exit the cowl. The rear face of the core is also within 3-4 inches of the oil pan, so the exit area is restricted. In other words, I don't think the core itself is to blame. Unfortunately, without expanding the cowl in the downward direction, I can't see a way to improve the geometry. Fortunately, that is a fairly reasonable solution, and would offer some other benefits, such as increasing the cowl exit area, and being able to fair in the muffler to some extent.

My actual plan is to (eventually) use your ASI trick on both rads, and the oil cooler. I assume the water cores are getting a much better pressure recovery than the oil core is. If that proves to be the case, and since I still have some excess water cooling, I could swap the roles of the right cheek core and the chin scoop core. That would make the left cheek and chin cores water, and the right cheek core oil. This option isn't without it's own problems when it comes to running hoses.

With any luck, I'll have my repairs complete by the end of next weekend (Oct 3rd), and will get back in the air. I've blown off all the other fly-ins with Shady Bend being my only goal. It's going to be close, but I still might make it.

Cheers,

Rusty (surrendered Slingshot data plate, and airworthiness cert- just parts pending rebuild and recertification now)