#4 Coolant Mod
Undoubtedly one of the easiest coolant mods, this will directly inject cold coolant to the #4 cylinder. This is important since the head coolant flow leads to hot stagnation with high horsepower motors.
TrboVan used 1/4" pipe on the waterpump housing and the head. A straight hose barb on the waterpump side to clear the Alternator bracket and a 90 degree hose barb on the head side. These were connected with -4an hose. Make sure to use the appropraite drill bit size for 1/4" pipe thread.
(now need picture of the hose installed) (pics from Bryan Lugert)
BFnGA says that when drilling the holes into the head and water pump, start with a small drill bit and drill it incremently larger. He used a 3/8" NPT for his setup with a 7/16" drill bit.
(need to get pictures from BFnGA of his setup... )
Additional Notes:
Originally Posted by cordes
Frank