<VV> Test for Oil transferring heat .

[Mel Francis]

Glad that you mentioned this Mark,

The ex-Sebring GT3 Corvair we brought back from Florida has two big
10" x 10" oil coolers with fans, one mounted in each rear quarter, with
large-bore hosing plumbed on a parallel circuit. It runs a high capacity 
sump,
a high-volume pump and remote filters. The entire setup was obviously
designed to shed large amounts of engine heat in those Southern Florida
enduro racing events.

Now that the car is up in Wisconsin, we're installing an oil-stat, with the
central bulb made to open at 205 degrees, so that the oil will be within its
proper temp range, 210F -250F, before it is sent down the lines. Of course,
for most events up here, we may only need one oil cooler. I'm also
looking at adding a piston-cooling oil spray setup, so that even more
heat can be transferred to the oil. This process will help the engine 
achieve
its design-temp range very quickly and carry even more heat out of the
engine to these large coolers. When the entire system is up in heat-range,
and the oil viscosity has dropped, you can feel the heat coming off the back
of the coolers, just like a regular water-radiator. Getting the viscosity of 
the
oil down, appears to be the best way of increasing heat transfer at the 
cooler.

I figure if it was basically oil-cooled in Florida, then let it continue to 
be
oil-cooled, even in these cooler northern climes. The racing engine has no
lower shrouding, so it needs to be able to build and hold heat in the engine
at a stable temp, then offload it through a large remote radiator.

Mel Francis

----- Original Message ----- 
From: "Mark Durham" <62vair at gmail.com>
To: "John Howell" <32chevy at 0306.org>; <virtualvairs at corvair.org>
Sent: Sunday, February 05, 2012 1:40 PM
Subject: Re: <VV> Test for Oil transferring heat .


> John, thanks for your support on the fact that the oil in a corvair
> engine Does play a roll in removing heat from the engine. Everyone will
> note that water cooled engines do not need oil coolers because the
> water cooling system keeps everything in the design temp range for the
> engine and oils in use. However, the air cooled engine is different.
> The internals would experience over temp because the overall temp of
> the air cooled engine is 125 to 150 degrees hotter in normal operation.
> So an oil cooler was added to pull the heat out and keep those internal
> components in there normal temp range, including the oil. Again, I
> refer to my experience on air cooled aviation engines which use larger
> oil coolers that are not enclosed in the tin like the Corvair so it has
> a continual flow of air, and in 200 hp plus engines, you start to see
> spray nozzles that spray the bottom of the cylinder bore and pistons
> and rods expressly for cooling purposes. I have seen engines fail
> because one of those spray nozzles plugged up. The piston end of the
> rod turns blue and the piston pin seizes, then the piston wear
> accelerates, not a pretty sight. Mark Durham
>
> Sent from my Windows Phone
> From: John Howell
> Sent: 2/5/2012 9:18
> To: virtualvairs at corvair.org
> Subject: <VV> Test for Oil transferring heat .
> NOTE:  I don`t think that you will have to be a petroleum engineer to do
> this test.
>
> Next time you change the oil in your car warm the engine up good before
> you drain the oil.  As soon as you drain the
> oil into a catch pan stick your finger into that oil and see if the oil
> removed any heat from the engine ! Ha!
>
>
> John Howell