Well, its been about 30 years since I've built an engine that is race-only (not street driven), but have built a lot of street driven engines in-between. On the 493 that we just picked up (Bounty Hunter Clone Car), the water outlet did not have a thermostat (not surprised). Back in the old days the thought was to run a restrictor in the thermostat housing (sold by Moroso) to slow the flow of water down through the engine so that proper heat exchange would take place (in both the radiator and from the heads to the coolant). The car has a Moroso motor driven water pump so I don't know if this thing would flow enough water to even need a restrictor. What is the general consensus today?

Also, on engines that don't use a thermostat, a good friend suggested that I plug the by-pass hole in the water pump housing (just below the water outlet) as this will force all water through the radiator instead of recirculating hot water back in the block. This trick is supposed to help the engine run cooler. Thoughts?