mtnman82

So, do all the Mahle's have the anti-drain valve? Does the Porsche 928 filter (from Dfastest's posts I gather it does not)?

HIGHBOOST

zermatt,

awesome thanks for that explanation. Why is it easier for pressure to build up when starting the engine with having oil retained to the oil filter?

zerMATT951

Because the engine doesn't have to fill the filter with 1qt of oil immediately on startup. The oil filter is in the "pressurized" part of the oil circulation system. Anything that gets pressurized must first fill with oil before oil will start effectively flowing throughout the engine.

zerMATT951

I've never looked at a 928 filter, but the Mahle OC142 does. Since Porsche mounted our filters tilted down, I would expect that any filter recommended for our cars would require an anti-drainback valve.

DFASTEST951

I'll have to check to see if there is any hesitation longer than normal with the 828 filter.
420whp, could you keep me, us informed on the CM Racing filters. I'm really interested in them but if the anti drain flap craps out as stated on here, I'd like to know. Thanks.