The Cadillac STS-V intercooler cooling system holds a total of 2.6 quarts of coolant. That’s 0.65 gallons. The benefit of having little coolant is that it heats up quickly, and it cools down quickly. However, I wonder if there is more disadvantage to such a low coolant capacity. The LS9 engine in the ZR1 has a small rectangular intercooler coolant tank inline to hold more coolant. D3 offers a small cylindrical reservoir for the STS-V to hold more coolant and reports good results.
I have ordered one of these AVS tanks hoping I can find a good spot to fit it:
The tank is 15.5″ long x 3.5″ diameter with fittings at each end. The 1/2″ fittings will be a bit of a flow restriction for the 3/4″ inner diameter intercooler hoses.
For my next experiment I a hoping to use the OEM heat exchanger with a front mounted heat exchanger in series. That in itself will add 1.9 Liters (2 quarts) of additional coolant inline. But I’ll get the tank in hand and see if I can figure out a place to mount it for an experiment another day. Then we can get some real data to answer this question.