Subject: My new rad

This is a stock $200 single pass all aluminum Summit Howe racing rad
modified
by Ed Klepeis to a two pass design. The core is 15 inches wide
and 24 inches long 2.25 inches thick. A bit overkill for an NA
engine if you do the ducting right. I will go turbo eventually
so I think I will need the extra core volume.

Paul Lamar

Now if he could modify a rad to make a double pass with flow divided
front to back we'd have something - counter flow.  I had asked Ron
Davis
racing to do mine that way, and had been assured on the phone that
they
could.  When I got the rad it was standard two pass side to side.
They
then tried to convince me it wouldn't make any difference.

Al

Looking at what he has done in the past I am sure Ed could do it Al.

Maybe it won't make a difference as the continuos fins still connect
the tubes
front to back and conduct heat from the hot side to the cool side
defeating some of the purpose.

IMHO the best thing to do is use two thinner one row rads back to
back
for the counter flow advantage. If you decide to build one I can
check
water temps in various places in the rad and other places in the
cooling
system on the dyno.

I discussed this with Ron Davis in person in AZ at length and I could
not get him to see the advantage.

I suspect that ultimately this will prove to be the best solution for
aircraft use as it will cut the frontal area of the rad and make it
easier
to fit under the cowl.

Paul Lamar

Paul,  this is exactly the principle behind the C & R Scirrocco rad.
Two one inch cores separated by 1/4 inch.  They believe in it.  Jerry

Please take some pictures for me.

Paul Lamar

Here is one pic.  I have drawn in the 1 inch cores.  They are separated
about 7/16 inch.   Griffin uses two 1.25 cores without the gap.  C & R
claims their smaller cu in rad does a better job.  It was a matter of
trading cu in for air flow.  I went with the flow.  Jerry

Looks like they copied my idea as I published it on here a couple of years
ago. :)

Paul Lamar
 
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