Back in August of last year I contacted Ron Davis for a custom
rad that looked like this. At the time he claimed he had the same idea
and was in the process of patenting it. When I was in Phoenix earlier
this week I visited Ron and asked him where my rad was. He told me
he received a patent and had built and supplied several to Nascar
racers and they worked great. I confirmed my order so hopefully
I will have my custom rad in a month or so.
This is what is called a cross counter flow rad. The rule of
thumb with rads of finite thickness is the first half of
the rad does 3/4's of the work as the difference in the air
temp and the water temp becomes nearly equal as the air flows
through the rad from front to back and absorbs heat. It takes
a considerable difference in air temp and water temp or there
is no heat transfer.
This design addresses that issue. The hot water is first passed
through
the back half of the rad and then through the front half in a two
pass configuration. This maximizes the temperature difference thorough
out the rad. The trick here is the front and back half's of the
rad are thermally isolated from each other by minimizing the
metal conduction paths. To not do this defeats the intent of
the cross counter flow design.
There is no weight penalty or pressure drop penalty in either the air
flow or the water flow with this design. The cost is only slightly
more
as the same number of fins and tubes are used. In theory a slighly
smaller rad (less cooling drag) could do the same cooling job.
Paul Lamar
Jerry Hey wrote:
Looks like a real break through. Simple and effective. How do I
get hold of Ron? Jerry
Ron Davis Racing Products
7334 N 108th Ave Glendale AZ 85307
1 800 842 5166
Ron also has an Aluminum radiator fill neck for $21
part number 8601 and a Stant Racing Cap for $15.75 part number
8603.
BTW one of the main reasons I wanted a two pass rad was to get the inlet
and outlet on the same end :-)
Paul Lamar
Paul,
Ken Gillanders wrote:
Mind telling us what the price is for your new rad?
Ken Gillanders
BD4 Rotary Powered
Ron davis got back to me and he quoted $770. For half that price
you can buy two new cores and have a welder weld it up.
Heck you can buy an all aluminum NASCAR rad for under
$200 from Summit or Jeggs. No thanks Ron Davis.
Time to practice my tig welding on some junk rads
Paul Lamar
marc wiese wrote:
Paul,
Somehow I deleted your design for this radiator. I would like to look at it
again and muse upon it. Seems like a good idea to minimize the space taken
up. How about drag-how think would it be-2" min or more?
Marc
--
I went with the $200.00 rad but here is the drawing again.
The drag would be the same as any other rad its same size.
The potential is if it works better it can be made slightly smaller
with slightly less drag.
Paul Lamar
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