So, I see the choice as:  Do you want an 'efficient' radiator or an
efficient airplane?

Tracy Crook
-------------------

This probably does sum it up very well.  This has to be one of the best
discussions that I've seen on the list.  On the other hand, if it's so
great, why do I still not have a radiator :-)

I talked to C&R Racing yesterday, and they offer a number of core
thicknesses, but most are single row designs.  They have the usual 2 row
core that's about 2.5" thick, and also a wider 2 row core that's about 3.5"
thick.  What they make for the NASCAR folks is actually 2 of the 2 row cores
welded back to back, for a total thickness of 5.6".  These are double pass
units, with oil coolers in the intermediate tank.  Now for the bad news,
they weigh about 40-45 pounds dry, and cost $1380.

After reading all the info, I have to agree that the thickest core would be
the best from a drag standpoint.  Unfortunately, it will require a more
ideal ducting to make it work properly, and low speed performance will be
degraded, especially if you don't have a nice effective cowl flap
arrangement.  Realistically, I need to forget about really thick cores,
because I will probably not be able to provide a proper duct to make it
work. This leaves me with the more common 2.5", or maybe the C&R 3.5" core.
I'll shoot for >1000 cu in of core volume, and try to use it with an
oil/water exchanger.

Thanks for all the great info!
Rusty