Mark71

Hey all... I am just getting back after having gotten a nasty case of pneumonia. It really sucked, but I am finally starting to feel better.

Anyhow, I have a question that applies to my DD (99 Ford, Duratec 2.5l V6) but also to my Cutlass because I want to relocate the filter on both cars.

The relocation kit I have (like almost all of them, apparently) uses a Fram PH8a filter. The original filter on the Ford is a PH2 filter. The Cutlass is a PH25.

The PH8a is a taller, higher capacity filter, but it has a much narrower, smaller center hole (which returns the oil to the engine). I measured both threaded filter openings with a caliper and it looks like PH8a is .695 inch and the PH2 is .815 inch. The PH25 is similar.

Could this cause a restriction to the point that oil starvation could occur??? I couldn't find any flow rate information for the filters in question, so I can't tell but the smaller return hole could limit volume.

Something else I thought of .... Do modern, DOHC engines flow more oil volume or less than my SBO? I would assume the SBO flows a lot more because of looser bearing tolerances, etc. but I am just guessing here.

Oh yeah, I generally don't use Fram filters. I use Napa Gold (Wix) but everybody knows the Fram numbers.

Allan R

Don't forget that you'll be adding enough line that you'll probably need to add around a quart extra oil each change. With the extra volume of oil, you should be able to get by with a smaller diameter center hole.

Before you install this kit, I would seriously address your concerns to the manufacturer of the kit.

Mark71

Has anyone else relocated their oil filter on the Cutlass? They must have had a similar problem... All the kits seem to take PH8A style filters...

That's a great idea. I don't know why I never think of just calling the manufacturer, but I will try that today and let you know what I come up with.

Mark71

I talked with Jegs today and found out a few things:

1) I am apparently the only person who's ever asked this question.
2) Flow rate on a PH2, PH25 is higher than on a PH8a, but the flow rates are at maximum rated oil pressure and this figure has a lot more to do with the restriction presented by the filter media - NOT the return hole size.
3) Almost EVERY relocation kit uses the PH8a / PH16 / HP-1 style filters because they are the largest capacity filters widely available.
4) Lots of people run the exact same relocation kit on race engines spinning northward of 7K RPM, so my daily driver is unlikely to have issues.

For more info, it appears the the Jegs kits (mine is #51715) are made by Derale, but the rep couldn't (maybe wouldn't?) say for sure.

This all sounds like good reasoning, but should I believe it? Does any one have an opinion for or against this reasoning?

Allan R

I am so glad you got the info directly from the manufacturer. The ONLY ONE who ever asked? Good for you! Maybe just the only one who phoned in is more likely. The info sounds ok. What you could do as a followup is send an email 'just to confirm' you didn't get mixed up on the phone. That way you have a paper trail in case there are issues. I would have no trouble accepting the info and installing it. You'll never be able to prperly evaluate its performance until you use it. Good job!

380 Racer

Just go to NAPA or some other parts store and buy a PH8A comparable filter? I know with my System One filter I had to switch to a Ford threaded adapter and place the gasket in the Ford position also.

Is there really a quart of oil in two #10 lines about 3-4 ft long each?

Allan R

That's a suggested amount based on some web research. It obviously depends where you mount the new fitting to determine the amount of line and its capacity. Probably different for every application.