That's exactly what I'm doing, Rusty. When you consider 30% of the cooling
is
done by the oil cooler, so the radiator has to be sized accordingly. The
installations I've seen in the past never had a large enough radiator and
enough heat exchanger plates installed. For my NA installation, I'm going to

try around 1000 cu. in., this is based on around 2400 CFM flow. I'm pretty
confident it will work with proper intake and recovery ducting, well see.
Sure
will make installation plumbing easier. It will require oil bypass for
temperture control(check out C&R Racing) Fred
-----------------------------

Good points Fred, and math that I can actually use :-)  

I've been a bit fixated on radiator sizes for only water, and didn't
consider the oil cooling capacity in my size. Here's how I see the sizes:

Ed's two evap cores- 680 cu in total
2nd Gen RX-7 oil cooler- 180 cu in.

This gives a total of 860 cu in for oil and water. My originally planned 18
x 18.5 x 2.5 core gives a total of 833 cu in, which should be plenty for
water, but could be on the small side for oil and water.  My next option
would be an 18.5 x 22.5 x 2.5, for a total of 1040 cu in.  Unfortunately,
the larger core would be pushing the limits of my cowl size.  I'll have to
give a bit more thought to this.

Thanks,
Rusty