These are the small diameter filters. The Wix 51061R mentioned only filters to 61 micron. Although it's not listed on the Wix site, one of their reps also suggested the 5122R, etc only filter to 60 Microns.

I've always avoided Fram in the past, but the HP6A filters to 12 Microns with 20 GPM flow. I may be reconsidering Fram for this application.....

I have HP6a's. They look like a pretty serious filter compared to a regular Fram. They seem hard to get, summit racing has them back ordered right now. I ordered a couple of
moroso hp6 racing filters from CP. anyone have any experience with them?

I use the Donaldson P550832 from Amsoil. It has the flow of the racing filters and super fine filtration, the best of both worlds.

Moroso 22465 - Moroso Race Oil Filters

http://www.summitracing.com/parts/MOR-22465/

Not so. You said you liked the K&N but was concerned about the low 11-17 psi bypass. The HP 6002 has no bypass. I run no bypass valves in the block either so all my oil goes through this filter. No problems.

+1

NAPA GOLD 1794 is made by WIX and has no bypass. 20 micron filtration and 9-11 gallons per minute. Good overall filter. Easy to find.

WIX Racing filter!

my engine builder loves NOx and Fram oil filters !!!!!!

Amsoil offers 3 filters, I use the BIG one, it holds almost 2 quarts of oil. I am a dealer and could set you up to buy it yourself. I don't have the number in front of me but I can look it up pretty easy.