ZR-1 Net Registry Forums

Quote:

Originally Posted by bradslt5

could one use breathers instaed of having the system closed . if the car was going to be used as a drag car only

your better off keeping it closed & at least try to keep some negative pressure (vacuum) in the crankcase. you won't have any manifold vac. at W.O.T. of coarse, well next to none, but you will in the staging lanes & after your burn-out. will an open system (breathers) you'll never have any crank. vac. at any time. the whole idea is to keep the cylinder walls clean, the rings stable & keep the oil away from the rotator (crank, rods). with breathers you may not build up any pressure but you'll never build any crank vacuum either & that's the goal. on the better stuff i do, 2 H.P. per cube & up, i generally turn the rear main seal around, backwards, because i'm trying to run so much crankcase vac. it will flatten out the seal & pull in fresh air. this way the more water depression, vacuum, it will tighten up on the crank. that how important vacuum is to me. it's kinda a tough deal with the LT-5 having so little volume but venting into the atmosphere is not the answer if a guys looking for power, IMO.