George Lendich wrote:

Better to have just the extra oil capacity.

George 

Maybe I am taking the above statement out of context, BUT...for the sake of any newbies here, I Just want to make something perfectly clear here:
 
Oil (or water) capacity has NOTHING to do with cooling ability. It only increases the "inertia" of the cooling system... if you dont have enough heat dissipation through the rad or cooler, you will still overheat. A larger capacity will simply mean it takes longer for that to happen, but it WILL happen. The dual cooler setup on the renesis is there for a reason. If you make enough HP, you will also make enough heat to probably require the second cooler. You will have to dissipate that heat.
 
The aux oil cooler I have here has what appears to be a thermal bypass valve in it. When the oil is cold, it bypasses at the cooler inlet to the cooler outlet. As the oil warms up, it is routed through the cooling surfaces. I dont understand how a properly designed oil or water cooling system can over-cool.
 
Just my 2 cents
Dave