Shimming Factory Oil Pump Relief Valve

[r33_racer]

Im curious if anyone has done this when using their std oil pump and if so, do you know roughly what thickness shim will net what oil pressure increase?

Cheers.

[The Dan]

Im curious if anyone has done this when using their std oil pump and if so, do you know roughly what thickness shim will net what oil pressure increase?

Cheers.

I normally use a M6 spring washer that I straighten. I think they are about 2mm thick and it get's you roughly 10-15psi on cold start and in the top end when hot but doesn't seem to make much of a difference at idle when hot though. If anything it might be 2-5psi idle/hot

[irishGTSr32]

I normally use a M6 spring washer that I straighten. I think they are about 2mm thick and it get's you roughly 10-15psi on cold start and in the top end when hot but doesn't seem to make much of a difference at idle when hot though. If anything it might be 2-5psi idle/hot

this the done thing? any probs wth doing it?

[r33_racer]

Cheers Daniel! Exactly what I was looking for.

[The Dan]

this the done thing? any probs wth doing it?

Never had an issue mate. It's more or less just to help out a 15-20yo spring

[lachlanw]

why ?????

[The Mafia]

I shimmed mine 2mm, DaleFZ1 has done the same thing.

[The Dan]

why ?????

Why not ?????

[boostn32]

does this apply to any RB oil pump?

[The Dan]

yeah pretty much. Why's that?

[boostn32]

just didnt know if it was a done thing for all the pumps, i have a 26 pump on my 20, would it still be any better with more

pressure on the valve?

[The Dan]

just didnt know if it was a done thing for all the pumps, i have a 26 pump on my 20, would it still be any better with more

pressure on the valve?

Unless your motor is out of the car, there would be no point doing all that work for such a little gain. I only do it as a small aid due to the fact the 20 year old pump can do with a bit more oomph. The oil pressure increase is not really going to do too much for you.

Also, there is no difference between a 26 pump and a 20 pump unless it's an N1.

[boostn32]

engine is out of car, does the pump need to come off to do this?

[The Dan]

engine is out of car, does the pump need to come off to do this?

No but the sump does

[SECURITY]

they do this to rb30 oil pumps. its a common "fix" for the lower oil pressures the RB30E pumps produce at higher RPM when putting a DOHC head on an rb30 compared to DET pumps (for getting away with using a RB30E pump rather than buying a DET pump)

Edited March 17, 2010 by SECURITY