Oil cooler in/out

I saw Allan's video on Preston Brown's car. Very nice indeed. I have a question. I noticed that the inlet/outlet for the oil cooler is located on the top of the cooler. Is it a problem if those are on the bottom? Even though I have an Accusump, I am wondering about the oil from the cooler pooling in the engine? Should those connections be on the top of the cooler, or does it really matter?
In my experience with other race cars it largely shouldn't matter, but putting the fittings at the top MAY be preferable as it doesn't allow the oil in the cooler to drain back into the sump (or wherever) on shutdown.

Bill Musarra

The oil on fill or pumping would have a difficult time getting all the air out of the cooler. The top mount would insure the full area being utilized. On the negative side when changing the oil the used oil would remain in the cooler. Need to add a drain valve on the bottom of the cooler to insure total emptying


Howard Jones

Earls shows them in the up position on their installation drawing for what that's worth. I didn't do my GT40 that way because of hose lengths and packaging issues. The only other thing I can think of is the cooler is pre loaded with oil on startup so the only thing that needs to be filled is the lines. How much of a big deal this is I don't know. My hose at the bottom setup hasn't had any adverse effects in 10 years.

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Improved Racing makes a nice adapter for LS motors that allows you to run oil lines to a cooler and control oil temp all in one.
It doesn't make any difference in out location on the cooler, just make the plumbing easy.
When you cut the motor off the oil starts to drain back into the motor from the oil tank.
GM says to check oil level you should get the oil up to tempature wait 5 mins them check oil level.
my inlet and outlet for the transaxle cooler are both located at the top.
If you look in this video from 2:28 to 2:56 showing the engine oil cooler and Accusump you can see the connections... there appears to be two top connections and perhaps a bottom connection (at 2:37), maybe because of the Accusump?.
Sorry for the lack of specifics as I didn't do the install and I'm ignorant.


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Edit for above...perhaps what looks like a connection at the bottom of the engine oil cooler is actually a connection for one of the hoses coming from the top of the cooler!