4 stroke filters

[justatip]

The AC PF1127 oil filter is a type of filter that can be used on many 4-strokes. Even better is the AC Ultraguard Gold filter, UPF1127. This is the type of filter used on Corvettes, and is probably the best filter one can buy from any source. Better filtration and better flow rates when oil is cold. Now, rumor has it that the Ultraguard Gold filters are no longer being made by AC. If you use or want these filters, I suggest getting a supply ASAP. I just bought a case with great trouble. I use them on my Yamy and they are the same for Merc 90 (and probably 115, 75, too).

Check filter X-Reference to see if the UPF 1127 will work on your OB. If so, this is best filter you can use, in my opinion. Yes, at about 10$/filter, they are not cheap, but given the value of an OB, I believe they are well worth the price, even if you use one every other change.

[Gearhead]

Interesting information. Any idea how the "better filtration" occurs? By better, we assume decreased mean (Xbar) particle size (in microns) capture? Typically, filter elements that retain smaller particles do so at some loss in flow. Grade of oil, viscosity, pour point, and age of the oil would likely have an effect on flow. Is this filter designed with higher internal working pressures in mind? If so, is your motor designed with the bypass valve of correct relief pressure? Or does the Ultra have extra filtering media, but of the same size? I'm thinking this may be the case so that decreased flowrate or higher bypass ratio around the filter doesn't occur. Given that scenario, it wouldn't filter out smaller particles, but would have an opportunity to capture more particulates per pass thru the filter. Ever cut one of each of them apart to inspect? Would love any info you have to share. We all could benefit from the added knowledge. Right now, I'm using the OMC part from my dealer so as not to have any questions if warranty service should arise, but if the Ultra is really better, I might want to change over to it once my warranty period has expired. Thanks for the tidbit of info, and if you have any more, please post it!

[justatip]

Cold flow through the media is better, according to AC. It also has a higher burst strength and better media (synthetic composition). Search www.acdelcotechnet.com for more information. I have cut apart the filters and it seems they are made better. I read on other web posts that the drain-back valve is included. As with investments, do your own DD, but I will continue to use the Gold's. If you look for them, try a GM dealer. Only 1 or 2 autopart's stores carried them. I think Pep Boys is one. They have not dealers near me so I just bought from my local GM parts dept.