Oil pump Mod: - pictures.

Does this look / sound about right?

Thought I would throw out a pic of the port job I did to my oil pump yesterday. I searched these forums high and low, and couldn't find any information on exactly which hole to bore, or how big to bore it. So I took my best engineering guess and did all three The yellow arrow points to a small hole on the bottom of the oil pump that lets oil drain between the oil pump and the front main seal. I believe this is the hole that SP recommends enlarging to prevent the blown FMS problem. Anyway, hope this helps some people in the future searching for oil pump porting!

Can you do some close ups of the pressure relief valve (both in bits and assembled), and the backplate?

I take it the big port on bottom left is the suction and the smaller port on top left is the pressure?

Can you do some close ups of the pressure relief valve (both in bits and assembled), and the backplate?

 

I take it the big port on bottom left is the suction and the smaller port on top left is the pressure?

Well this isn't my picture but I was planning on doing the same mod.

I was after anyone who has done this, and had PLUS+ results with it.

Well this isn't my picture but I was planning on doing the same mod.

 

I was after anyone who has done this, and had PLUS+ results with it.

Well if it helps I've have done 2 engines for a test with a totaly stock pump but only drilled the seal hole and they have been fine with raised rev limits. There is a saying that the relief hole creates high presure due to not being able to flow but then the pump was never made to go above stock RPMs and above the stock rev limit I personaly like the fact there is the higher oil pressure .There are also bigger restriction outside the oil pump that need looking at. Also if you take ald old pump apart have a look at the gallery. Even if you drill that hole by the time the back plate is back on the bulge in the gallery now becomes the restriction as it's actualy narrower than the hole you plan to drill there fore only moving the problem on. The seal one is defo a good one to do . There is also the spring mod to reduce pressure ..that also scares the hell out of me ..high RPM demands enough oil supply IMHO

Interesting, so just to clarify, which hole do you recomend doing what to... im prob being stupid here but I cant quite see where....

the Front main seal drain hole..marked in yellow in your picture.

so what rev limit is safe to use without cutting engine life in half?

I agree with Mig. As large a hole as possible to vent the area between the front crank seal and the rotor is a good idea (as long as you don't go mad and permanently connect your oil pump to the sump )

As for safe rev limit, its a big subject that has been discussed a few times before. If you are talking about a safe rev limit just from the oil pump perspective, I reckon you'd blow something else up long before too much oil pressure became an issue.

Got my oil pump stripped and was checking what diameter I should drill the seal hole?

I know 0.204" is 5.1mm but that is the size I have already, how much bigger should I go?

Anybody know the answer?

It seems there may be 2 revisions of this pump, I'm looking into this now as I have 2 pumps here with different siz holes. Looking at the Subs part number there is, but I need to check closer.