Spin on oil filter adapter gasket? SBC

[John Milmont]

To make a long story short, I'm currently building a sbc 383 stroker and have to install a spin on oil filter adapter. This is the one I got:
Allstar Performance ALL92000 - Allstar Performance Oil Filter Adapters - Overview - SummitRacing.com

Now, common sense would say that I need to put a gasket between this thing and the block. But, there is no part number for the gasket. I was thinking of just cutting one out of gasket paper and making due; but I noticed a small ridge cast into the bottom of this where it meets the block (its all cast aluminum). I'm wondering if this part gets crushed and makes the seal and therefore doesn't need a gasket? Or maybe it just doesn't matter that a little oil gets by? It looks like this once installed...

 

[Mike Huddart]

No gasket required, most of the oil goes through the by pass anyway if you are using a single filter.
A word of warning when using those Allstar ( Chinese ) adaptors, the by pass "flap " doesn't fit as well as the original GM ones and if you rev the motor stone cold the flap tips over and jams permanently open so you get no filtration. Either be carefull with warm up or use one of the racing type fiters, like the Wix, that pass oil ( and crap ) easier........or refit the one in the photo !

Mike

 

[John Milmont]

Thanks for information.

When I was looking at these adapters, they also sold ones that had no by-pass at all. I was thinking that would be the way to go but I went with this one because I thought it was "safer". Should I have gotten one without a bypass? I guess I could plug the bypass hole on this one...

 

[Mike Huddart]

You COULD plug it but be sure to make friends with your local crank grinder because you will need his services sooner or later.
Mike

 

[John Milmont]

So i was pushing down the little bypass flapper to see if it could get it jammed up and i wasnt able to. But during this, I noticed that the spring pressure seems really weak - i mean it must be something like a 5lbs spring. What is this spring supposed to be?

 

[Jac Mac]

So i was pushing down the little bypass flapper to see if it could get it jammed up and i wasnt able to. But during this, I noticed that the spring pressure seems really weak - i mean it must be something like a 5lbs spring. What is this spring supposed to be?

About that, the area of the little flap valve is about 1/4 or 1/5 of a square inch therefore if the pressure you 'feel' is about 5lb then it will take around 20/25 psi to open it which is the whole idea making the majority of the lube pass thru the filter element until it gets blocked up enough with crud to the point that the by-pass then opens so that the motor does not die straight away.

GM stuff seems to have the by-pass built into the pump body or block adapter in this case, Ford filters have the by-pass at base of element in the actual filter

 

[Mike Huddart]

Not strictly true, no single filter will pass enough oil, particulaly when cold, to supply an old style V8. Especially those small filters on stock Chevys, the PH30 type, at high revs some oil will go through the bypass even hot.

John, the disc valve tips sideways under the flow of oil when cold and sticks sideways on in the port, never seen it happen in a stock GM housing, only the aftermarket ones.

Mike

 

[John Milmont]

I'm thinking of just plugging the bypass and then just getting a filter that has a bypass built in like the wix... I had no idea how much of a headache this one part would cause.