Paul, You mentioned a radiator supplier for custom sizes
 > other than Griffin. Said there was "no epoxy used". Didn't
 > manage to save that one. Who are they? I think Lynn
 > Hanover used them as well. Bill Jepson

I use Griffin. Cheap, and no problems.

Lynn E. Hanover

Lynn, I know they are welded or brazed but don't they also use epoxy
around the base of the tubes? I might add it was Griffin that supplied
the oil cooler that split in at least three instances resulting in two
in-flight fires and one seized engine resulting in a fatal crash.
I suspected it was made in China. Use only oil coolers that have been
tested at well over 100 psi. Or just use the stock Mazda oil cooler.

Paul Lamar

Being familiar with those cases, I will just say this: if you don't
design the installation properly, and don't specify what you need to

the

maker of a custom cooler, you can't blame the maker.  Griffin makes
their own oil coolers.

I have a custom Griffin oil cooler that I'm impressed with (the stock
Mazda not big enough for a 20B).  I specified 125 psi operating
pressure; it was tested to 150 psi.  It hasn't flown yet, but I have
reason to be optimistic.

Al

That is different than the Griffin oil cooler I saw that failed. The one
I saw came in
a Chinese card board box. I know Chinese card board when I see it as I
used to sell
clone computers. :)  Yours looks pretty good. For other people
installing a three rotor what did it cost?

Paul Lamar

Al Gietzen wrote:

Cost $514.00 (Feb,'02).  The quote for 2-10 units was $441.00 ea.  I
thought the price quite reasonable compared to other quotes, and better
than the $$597.00 for an 11.5 x 16 coolant radiator from Ron Davis
Racing that I'm not impressed with.

The oil cooler core is 5.5" x 21.5" by 3.25" thick.  Internal turbulator
tubes, 14 fins/in.  I know you think it's too thick, but Griffin quotes
1.48" h20 airside drop at 1600 cfm (about 40 fps [27 MPH] air flow velocity.  I
did my own measurements and got 1.25", so I believe it.  Oil side PD [pressure drop]
quoted as 27 psi at 18 gpm.  No double check on that.

Al

Interesting data Al thanks. The RX8 200 HP has one rectangular oil cooler
about 8 or 10 inches square mounted just ahead of the left front tire
and just behind a large scoop. The 250 HP version has two. One on each side. 
There are no stone gards in front of them so new ones will be a popluar
item in the parts department for a few years not to mention ruined engines
that have been run with no oil pressure as a result of FOD :)
First think I am going to do is make a screen to fit in the scoop hole.

Hint hint... Jim.

Paul Lamar
 
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