In most instances, getting more horsepower from your engine requires "leaning" on it with non-stock performance modifications. Higher compression ratios and bigger-lift camshafts produce increased power, but they also produce added heat as a byproduct. The usual result is overheating, problematic starting and detonation.
Correcting an overheating problem usually involves upgrading the cooling system. Many car crafters go for the big-ticket upgrade items--custom multicore radiators and high-flow race-type water pumps--but they fail to start with the low-buck basics such as determining if the radiator is plugged or if the stock water pump is circulating water at full efficiency. In many instances, the water pump alone is the overheating culprit, because it isn't moving enough water--and the volume of water it is moving cavitates during mid to high-rpm engine operation.
An easy way to solve this is to install a Flow Kooler water pump disc (available from various mail-order outfits) to the backside of the impeller on your stock water pump. The install effort is minimal, the price of the disc is ultra low-buck, and the mod can improve water flow up to 30 percent. Follow along as we install the Flow Kooler impeller disc on the water pump in our Cheap Street Chevelle.
1.Remove the water pump from the engine. Begin the upgrade by removing the six bolts that hold the back cover of the water pump on. Once the bolts are out, pull off the back cover to expose the water pump impeller. | 
2.Set the Flow Kooler disc on the impeller, centering it over the impeller shaft hub. Then, using a center punch, mark the location of one of the holes to be drilled. | 
3.Using a 1/8-inch drill bit, carefully drill the first hole in the impeller. After drilling, remove any metal shavings that have accumulated. |
4.Once again center the Flow Kooler disc on the impeller, then use a Pop rivet (included) to affix the disc to the impeller. | 
5.Using the center punch, mark the next hole to be drilled. Then, just as you did earlier, drill a hole and install another Pop rivet. Follow the same routine for the third (final) Pop rivet. Remove any metal shavings or debris that have built up. | 
6.With the three Pop rivets in place, the Flow Kooler disc will be held firmly in position. Re-install the back cover of the water pump using a new gasket (GM PN 10204452), and you're finished. With the disc in place, the upgrade will prevent water from leaking past the impeller blades, which limits the performance of the pump. The disc increases water circulation and prevents water from cavitating within the pump housing, enhancing engine cooling--all for about five dollars. The discs are available for a wide variety of applications including GM, Ford and Mopar vehicles. |