Oil pressure relief valve,, OEM vs aftermarket

[AlterEgo]

GEN 2 busa
I have a aftermarket high pressure oil relief valve, when looking at it compared to the OEM it looks like same size piston, all holes look the same, etc...

But when comparing spring tension the OEM valve spring is a lot stiffer than the aftermarket.
I know there is more into the design of the aftermarket one than just spring pressure, but the pistons seem to be the same size. 

Anyone else ever compare aftermarket valve against an OEM valve?
What pressure can I expect from a new AM oil valve?
And what valve is recommended?

Thanks.

[Jay]

You can test them using a leakdown tester.

[AlterEgo]

Thanks Jay, you gave me a great idea, I'm going to fabricate a relief valve tester, complete with an oil reservoir and a gauge.

[Oz Booster]

Check flow/psi , i have never measured it but the original looks to be a lower cracking pressure and a restrictor still at higher oil pump flow ,
 

[AlterEgo]

Ok I fabricated a simple pressure tester with my $500 machine shop and here are my findings.  the aftermarket and the oem valves cracked open at 60 psi.  Both of them were wide open max flow at 125 psi.  Keep in mind this is not a scientific test, just a garage test.  Later i'm going to rig it up to flow oil and see what happens also I'm going to make a shim washer for the aftermarket spring to see if it raises the crack open pressure. and max flow pressure.

[AlterEgo]

Pictures

[AlterEgo]

More pictures

[sportbikeryder]

Looks like you are blocking the outlet ports almost completely with the adapter you made.

[Stainless1]

Nice test piece, thanks for the info.  Starting to crack at 60 seems about right, thanks and keep us in the loop for your continued research.

[AlterEgo]

Nice test piece, thanks for the info.  Starting to crack at 60 seems about right, thanks and keep us in the loop for your continued research.

Both of them started at 60, I would expect the high pressure one to crack open at a higher pressure.

[AlterEgo]

Looks like you are blocking the outlet ports almost completely with the adapter you made.

That's a restrictor so that when I use oil the air pressure wont blow it all over the place, maybe, but it does not affect opening pressure, and it will flow enough to open the valves completely. 

[AlterEgo]

So, now I put a 1/8th spacer under the spring, it now cracks open at 75-80 psi.  I think that's what I will install and see what the oil pressure is while running.

[Oz Booster]

How much does that change the open port area ?

A mate uses a specific size restrictor washer above his oil pressure reg , doesnt change cracking pressure but sure does change the pressure at high rpm

[AlterEgo]

How much does that change the open port area ?

A mate uses a specific size restrictor washer above his oil pressure reg , doesnt change cracking pressure but sure does change the pressure at high rpm

On the OEM regulator it opens uncovering the ports about 1/2 way then its blocked from opening more, on the Aftermarket reg without my spacer it opened and uncovered the ports all the way, now with my 1/8th spacer the ports are uncovered half way before the piston bottoms out, this could lead to too much pressure at high RPM, if so I'll run a very thin oil.