almost a given that anytime you do major high-performance work to a Corvette it will affect the overall operating temperature of the engine; the more ponies you squeeze from the mill, the more you’ll have to take keeping the engine running as cool as possible Such was the case with one of our project C5s that had some extensive performance work done to squeak 427 horses out of the engine. While the car always ran cool and never reached its normal 220° temperature even on the hottest of summer days when it was putting out a stock 345HP, since the mods were done it was not uncommon for it to reach 230°-235° even in 80° weather. While this condition isn’t critical, still, we wanted to get that temperature back down in the 215°-or-under range.