Thread:

Piston Ring ?

At what point do you need to run a vacuum pump ? Building a 468, 11-1 comp., 049 heads, 6.385 eagle rods, forged gm crank, looking at Mahle rings, they list low medium & standard rings, would I need a vacuum pump for a 15 lb. oil ring. Trying to free up friction but at same time want to stay away from added cost of the vacuum pump. Also building a 496 a after this build, wanting to go pro charger with a blow through dominator on the 496 , so trying to save a little coin for the big motor. thanks, Phil

15LBS seems OK for 4.31 bore @ WOT. +1 on pan-e-vac.

Originally Posted by gn7

Brand new late model cars are running 3 MM oil rings and no vacuum pump.
I would run a exhaust e-vac for sure. If not, then you need to consider standard rings.

1;ve seem 25 hp gain on the dyno with exhaust E vac