Does anyone have experience with oil temperatures before and after the
modification?


Thanks,
Dennis H.

I was just building a 12A engine and training the owners tonight and it is equipped with such an outlet. You should use a "Boss" fitting hole with straight threads. Tapered pipe threads will crack open the hole. The boss fitting will use and "O" ring and washer to seal the fitting rather than tapered threads. You may also want to replace the front cover to iron "O" ring with an aluminum pill with a .020" hole to supply the OMP if you use one, and a solid pill if you don't. So no failures there.

 

Use a small ball bit in your die grinder to blend the drilled passages into the kidney shaped pockets below the pump.

 

Discard the bug screen on the pickup tube. If the bug screen cover is one of those silver dollar sized things discard it and replace it with a flat disc about 5" in diameter to help protect against a vortex being pulled down from the surface of the oil. Trim as required to keep the disc from touching the pan. Warm the end of the tube with a torch and gently expand  the end of the tube about 25%. Lap the engine end of the pickup dead flat. Drill the attach bolts and safety wire. No gasket. No sealant. Check the end clearance on the pump parts. It only needs .004". If you have more than that, lap the engine end of the pump housing until you get down to .004". Clean and assemble pump. Pack it with Vasolene or similar light grease. So you get instant prime in startup. Actually you spin it with the plugs out until you have full oil pressure.

 

I seem to remember that a drilled 90 degree fitting has the same drag as 3 feet of the same diameter hose.

 

This mod makes sense and is fun to do. In race engines the front main bearing is fed with an identical fitting in the front iron. It will surly reduce oil temperature by some amount, but how much I have no idea.

 

Lynn E. Hanover