Lopresti WHOLEY COWL

[Michael Rath]

My Comanche 250 had the lopresti cowl installed when I bought it. I love the cowl. However, I noticed this summer that the oil temp would tend to run high. In the winter the temps are fine.

I had to call Lopresti about another issue and the oil temp issue came up. They said they had a new and improved oil cooler shroud and it would drop the temps.

I was just curious if anyone else with the old shroud switched to the new one and had better results?

The new shroud is almost $700 so I don't want to spend the money for a 10* difference.

[Hansmeister]

What does the new shroud look like?

[Michael Rath]

A picture of the new shroud is on Lopresti's web site if you click on the Comanche cowl link. I would post a picture of what I have now but I'm on the road and I can't post a picture from my iPad to the forum. I will get it up when I get home next week.

[Hansmeister]

I found the picture. They reference a new, larger oil cooler and the newly designed duct. I assume the $700 is for both.

What I have done to mine is add an aft nozzle, which seems to work very well. It's principle is based on solid applied fluid dynamics being applied to a flow problem. See picture.

[Michael Rath]

Nice, did you make that nozzle?

[Hansmeister]

Yes. Made from G-10 fiberglass sheet stock. Since then, reinforced corners and painted black.

[Kristin Winter]

Is the ratio of the exit hole to the cooler foot print critical? If so, what dimensions did you use?

[Hansmeister]

The area ration is 2:1.

[Kristin Winter]

Thanks! Any magic about the front to back dimension?