Block filter bypass valve

[earntaz]

OK -- this is a subject of dicussion all over the web ... so I ask the many experts here. What are the pros and cons of blocking the filter bypass valve on a LS-6 BBC? Thanks ... TAZ

[L78steve]

Are you ever going to let the maintenance go so long that the valve will need to open?
The valve is needed for cold starts with heavy oil also.

[VintageMusclecar]

Pros: 100% filtered oil all the time

Cons: If for ANY reason the filter fails or gets plugged, you have NO oil AT ALL.

The relief valve opens on a pressure differential. It only opens when the filter is clogged and becomes a restriction. This is an obvious benefit for those who never bother to change their oil & filter. If you stay on top of oil & filter changes you should never have a problem.

That said, in the event of some sort of fluke filter failure, personally I'd rather have unfiltered oil circulating through the engine than none at all.

I don't block mine, FWIW.

[novadude]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: VintageMusclecar</div><div class="ubbcode-body">Pros: 100% filtered oil all the time

Cons: If for ANY reason the filter fails or gets plugged, you have NO oil AT ALL.

The relief valve opens on a pressure differential. It only opens when the filter is clogged and becomes a restriction. This is an obvious benefit for those who never bother to change their oil &amp; filter. If you stay on top of oil &amp; filter changes you should never have a problem.

That said, in the event of some sort of fluke filter failure, personally I'd rather have unfiltered oil circulating through the engine than none at all.

I don't block mine, FWIW. </div></div>

I agree 100%. Probably one of the most hotly debated topics outside of &quot;manifold vs. ported&quot; vacuum advance. I firmly believe a working bypass is a good thing on any street / strip car.

[earntaz]

OK -- that settles it ... I will leave it as GM designed it.

Again -- thanks for the RAPID response by all ... TAZ

[GreenLS6]

Well... I Just finished an engine today for a gentleman with a 66 Chevelle - who's 325/396 just burned up due to the the BYPASS disk came out and went in the main oil supply Galley for the crank and cam.. ( BIG Metal Canister Style Not spin-on )
Took out the crank,cam,rockers, push rods... showed crazy good oil pressure the whole time !!! The pump goes thru the filter and pressure sending port on block then to the crank..

All my Pure Stock Motors - I take out the disk and spring, tap the whole and put a plug in it..
I just make sure I start it and let it warm to atleast 125* BEFORE I BEAT the CRAP out of it! [img]<<GRAEMLIN_URL>>/[/img]

Tried posting PICS, but says to big

[markjohnson]

Yep, I've pipe-plugged them on several motors in the past including daily drivers that were driven on cold winter days. Just been mindful not to drive too aggressively until the motor warms up. I've been told that the spring in the bypass is too weak and they are usually staying open with a lot of oil bypassing the filter.

[300deluxeL79]

i plug them off on the engines i've built, run the longer filter. the bypass valve opens at 12-15 psi, most of the oil will bypass the filter.

[novadude]

How many millions of Chevy V8s are running just fine with a bypass? What kind of filter are you running that you are getting a pressure differential of 12-15 psi from inlet to outlet? There is a lot less flow area in the passage feeding the filter than in the pleats of the media. How often do you think that bypass really opens? If the filter is restrictive enough to open the bypass than it will surely limit oil flow with a blocked bypass. I'd rather have full oil flow (bypassed or not) than restricted oil flow.

People overthink this stuff. For a street / strip car, just run the bypass and don't worry about it. Every single domestic OE V8 had a bypass engineerd into the filter like a Ford, or the adapter like a Chevy. It can't be all bad. My $.02.

[m22mike]

Good point