Don't take this as gospel truth, I'm just posting what my engine builder told me when we started to build my 340....that the 90 degree filter adapters, stock or aftermarket, have a number of bends within them, a tortured path for the oil to follow. I was told to use the shorter filter, or better yet, get one of the System One (looks like a trashcan) reusable filters.
Did you know, there are three different filter mounting studs, with varying restiction levels? I have seen 2 of these, the best one has the hex on the outer edge, wide open center...the worst, has the square drive center, it's the most restrictive.
The "good" one is supposed to be found in truck applications. Might be worth yanking a few oil filters off to get a good one from the "salvage and reclamation facility" (PC for yunkyard) LOL!
The filter plates vary also, some having as many as 8 drainback holes, and some as few as four. Drill a few extras if yours has less.
Remember, there is a gasket under the filter plate, Napa has them if the "other" store guys don't know what you are talking about....
Many people don't believe in using the high volume pumps, just using a standard volumn version, and putting the black high pressure spring into them. Worth a few horsepower. Smallblocks seem to have a problem, in that it's easier to pump the oil upstairs, than to keep it down on the main bearings.
I wish I could say I didn't find out the hard way.....
Thanks Mopar Action, that's where I read this stuff.
Hope this helps,
Alan627b
