[PunchT37]

I used to block mine. After swollen ac and wix filters, no more.


Better to have a short shot of "dirty" oil than to have a short starve of oil.

[Jay S]

Originally Posted by charlie66

So, am I understanding this right. When you use a roller cam and lifters you will not use a bypass in the housing and you will block it off? I'm asking because I'm using a roller cam in the build I'm doing now, and I'd like to know what's the best way to go.
Thanks

I don’t a run an external bypasses on roller cams. I block it and either run an internal in filter bypass that has a higher pressure differential (9-15 if a filter is available), or no bypass and make sure the pressure is measured after the filter. I try to keep full filtered oil in the oil galleys the best I can on all the roller setups.

[Skip Fix]

So far since the late 70s I have blocked them all. No problems with AC Delco nor Napa Gold. My 500 runs 75ish PSI at WOT.

[Jay S]

Originally Posted by HWYSTR455

Which filters do you use now?

.

I still use a lot of Wix. I am not anti Wix. But Wix’s over all trend seems to be to make them cheaper, not better. I have had may share of issues with them. I have collapsed a couple of them and blown seals out.

The main brands we use are Baldwin, Fleetguard, and Wix (including Napa’s by Wix). I prefer Fleetguard of the 3, then Baldwin. Wix gets used when the other 2 are not options.

Fram makes a very nice well designed race filter. They have a screened bypass. The latest Champion laboratories filters appear to be very well designed to. Hopefully they survive the bankrupcy.

[Dragncar]

I ran a Wix 1049 for years, no issues. They are the early 60s big car filters, larger than the one for a 69 GTO.
But the new 461 got a K&P 35 micron screen filter because of header issues. I then installed a Frantz by pass filter to get the small stuff. The K&P has a very high flow rate and you have the choice of a by pass or no by pass with their filters.
I plugged my adapter and got the K&P with by pass. I take my oil pressure and get oil for the Frantz from the 3/8" plugged spot by distributor.
It all works great.

[JSchmitz]

Don't block the bypass.

[charlie66]

Originally Posted by Jay S

I don’t a run an external bypasses on roller cams. I block it and either run an internal in filter bypass that has a higher pressure differential (9-15 if a filter is available), or no bypass and make sure the pressure is measured after the filter. I try to keep full filtered oil in the oil galleys the best I can on all the roller setups.

Do you do this because you're trying to keep material out of the needles or is there more to it?

[charlie66]

What psi will the bypass in the oil filter housing start to open. Does anyone know?

[Jay S]

Originally Posted by charlie66

Do you do this because you're trying to keep material out of the needles or is there more to it?

It helps to keep from collapsing a plunger on HR cams. On pressure fed lifters it keeps foreign material out of the needles.

On a flat tappet I don’t care as much. My Grandpa’s 61 Biscayne had a 235 that didn’t even have a provision on the block for an oil filter, the suction screen was all it had. Lol

Those old external bypass’s are usually 3 to 5 lbs to bypass them, and the oil still has to get to the filter. If the spring is 50 or 60 years old who knows what is it yet. Lots of oil goes thru that bypass even a cruising speeds with them. OEM’s got rid of that design for good reasons.

[charlie66]

Originally Posted by Jay S

It helps to keep from collapsing a plunger on HR cams. On pressure fed lifters it keep material out of the needles.

On a flat tappet I don’t care as much. My Grandpa’s 61 Biscayne had a 235 that didn’t even have a provision on the block for an oil filter, the suction screen was all it had. Lol

Those old external bypass’s are usually 3 to 5 lbs to bypass them, and the oil still has to get to the filter. If the spring is 50 or 60 years old who knows what is it yet. Lots of oil goes thru that bypass even a cruising speeds with them. OEM’s got rid of that design for good reasons.

Oh ok, I see why you block it now. If it's by-passing at 5 psi, then blocking it and just getting a filter with a higher bypass built in makes a lot of sense. So maybe I'll do that then because I'm using a roller. Sorry it is taking time to sink in. lol

[Jay S]

You can also buy an aftermarket filter housings that does not have that bypass provision and are designed for modern filters with an internal higher pressure bypass. I think it is a different thread filter than a standard Pontiac. I don’t remember if it is nightmare or KRE that makes it.

[PontiacHO]

Originally Posted by charlie66

I'm building a stroker 462ci for someone and I'm not sure if I should block off the oil filter housing bypass like HO had in there book back in the day. I always have done it, but over this pasted summer, with my own motor I had my Wix filters clasping one after the other. So, I'm just wondering if anyone else has had this happen to them with or without it blocked off?

Thanks

Maybe for an all out high RPM race engine but overkill for anything else. Filter media blown loose and pumped through the engine is more concerning with sudden volume of high pressure oil than the random chance of hard debris (metal). Blocked bypass had popularity but never proven to save engines that were on their way to catastrophic demise regardless.

[JSchmitz]

Originally Posted by charlie66

What psi will the bypass in the oil filter housing start to open. Does anyone know?

The bypass does not open based on absolute oil pressure. It opens when there is a pressure differential between the inside and outside of the oil filter element. An example would be a clogged filter element.

[grivera]

Originally Posted by Jay S

You can also buy an aftermarket filter housings that does not have that bypass provision and are designed for modern filters with an internal higher pressure bypass. I think it is a different thread filter than a standard Pontiac. I don’t remember if it is nightmare or KRE that makes it.

I put the link to the KRE one in post 15 - I have one on my 66 and it takes a standard filter:

https://forums.maxperformanceinc.com...1&postcount=15

[tooski]

I run a remote filter set up using a Wix 51515. Online information shows that it has an internal bypass.

[shaker455]

Originally Posted by PunchT37

I used to block mine. After swollen ac and wix filters, no more.


Better to have a short shot of "dirty" oil than to have a short starve of oil.

Can't put it any better than that Wade!

[KEN CROCIE]

For those "on the fence" regarding the bypass, I recommended doubling the bypass spring in the filter housing.

[Dragncar]

I ran a stock filter housing, no mods and a Wix 1049 for over a decade with a solid roller and had zero issues.
Street motor, leave the by pass alone IMO.

[KEN CROCIE]

the lee lf 24 had a coarse filter about half the size of the fine filter. There were two bypass valves. 1 valve opened to let oil flow to the coarse filter when the main (fine) filter had some flow resistance and a standard type of bypass with a normal function. Therefore, you almost always got filtered oil to the engine.

[Region Warrior]

Oh crap. 50 ys blocked bypass using delco filters(3 left-they still available?) Straight 30w.oil. Over 60k miles with100' burn outs. Pedal to the floor!