Update: I pulled out the ball and spring and replaced with a new plunger and spring kit. Now my cold oil pressure is 65psi. Much better than 100+. The plunger may not be the best deal but I think I'll run it for now. Once I get the car off the jackstands from all the other work and drive it and see where the pressure ends up, I'll know more.

Cool....but a pic of a completed item

Here is the ganged up templates. Again, everything I post seems to get stretched so dont go by it. You cut one out, wrap it around the oil relief valve, center punch and start drilling.

I'm having trouble visualising this....please post a pic of a finished one

I was wondering about that too: 3 x 1/2" holes is a lot of hole, for something that size.

Well, it leaves 4.5mm of spacing between them. I'd say that is enough to retain the relief valves rigidity but to allow any crud to not get stuck.

I'm not an engineer nor much of a mathematician for that matter, but wouldn't 3 12mm holes be a bit much for a 48.7mm plunger circumference?

I am not sure how insanely accurate this really needs to be but the reliefe valve I have in front of me has a diameter of 15.44-15.5mm, making the circumference 48.69468.mm Call it 48.7mm then? Can anyone measure theirs just to see?

If it does not need to millimetrically perfect, I have drawn up some plans and ganged them up on 8.5 x 11 paper. you can print (100% of course) and trim them out. There are a bunch on one page so you have plenty of chances to screw it up. haha!!

As I can never seem to post pix right on this forum, anyone can email me and I will send you the PDF.

EDIT: I just tried this and didnt factor in the paper thickness. Haha. Anyway, I added 1mm to the width and adjusted and it lines up very well. After cutting out, spray a little light adhesive on the back and stick it to the bullet so it stays put. Bonus, it should also protect it while you muck about with it! Cheers

I run a low idle around 650/700. I have a mech. Smiths 270 degree sweep gauge. Hot idle it bounces from 45/50. Cold start it pops up to 70 the settles at 60 off idle. After 30 minutes at 90 mph it settles between 55/60 and stays. Use of clearance between rod/mains and the crank journals can be used to aid engine cooling. Rod side clearance and thrust float can enter in. My 1360 Cooper S is a slow turning unit with a windage tray. While water tends to run high 190/200 the oil temp is always low in the 160/170 range. I'd love to flip those numbers. I wonder if keeping the tranny oil from splashing against the engine block is reducing oil temp? There are so many things to still wonder about. Steve (CTR)

You don't need a fancy adjuster to vary oil pressure.  A few suitably sized (ie one that fit washers inside the cap will increase pressure and larger ones (from memory copper sump plug washers are perfect) between the cap and block will reduce pressure. 

Cheers, Ian

Massively high oil pressure is a waste of energy and tends to wear bearing shells. MGBs had issues with this. For a street car, you don't need high oil pressure, and 100 lbs is too high. If you can't get it to rational specs with an adjustable cap, check every component from the gauge to the plunger, seat, use the old spring and cap to look for differences. The only thing worse than excessive oil pressure is a lousy gauge that makes you ink you have good pressure when in fact you don't. The stock mini mechanical gauge is very reliable. 

Keep in mind that the valve is usually fully closed when the engine is hot at idle, so if your oil pressure is low there, it is a reflection of the system overall.

Lastly, oil being pushed out when the car is driven hard is a reflection of poor crabkcase breather issues and has nothing to do with the oil pressure system.

Steve, what pressures are you seeing with that set-up? Should I get the adjustable cap so I can get my cold oil pressure down? Thanks

I also have the ball with the adjustable cap, but no amount of adjustment makes a change. Always 100psi. Making the spring shorter should lower the pressure which would be nice for the rocker arms. The good news is that all that pressure is not getting into the cylinders, I don't have to add oil to the engine. All that pressure is escaping out the valve cover cap occasionally when "someone" put their foot down. I thought the adjustable cap was a brilliant idea, and I was going to try something similar on my Austin Healey. But not perfected yet.

Jerry

Its just a real bugger to remove a seat from a manual car as they are smooth and difficult to get a grip on and often just have to be drilled out, cant usually even get a thread tool into them and you are really buggered if it snaps or you get swarf into the drillings. I have 2 autoblocks that I converted and used their spools (which are threaded) and welded up the cross drilled holes (oil flow in the auto is different). Since then I also bought a couple off the chap who wrote the modified autoblock conversion from Kevin Green's site - he sells threaded spools that are pretty easy to remove, just thread in a 5/16ths coarse and pull it out.

Thanks very much 66coop - a picture and template would be great!

cheers

Barri

You know the seat in the block is a replacable part? You can take it out and look at it. I have been running a ball with an adjustable cap. With a mech oil pressure gauge I can see the ball bouncing off the seat at certian pressures and RPMs. I'll have a look next time I'm in there. Steve (CTR)

So, shortening the spring will lower oil pressure hot and cold right? I'm good with my warm oil pressure and at idle in the summer I wouldn't want it to go down much.

You can remove the plunger and take a few thou off of the sides, polishing it in the process. It will not stick again when detritus meets it.

Pictures, too!

Ok, going back over my note:

You want 3, 12mm holes equally spaced around the plunger. I belive that is 16.5mm center to center to center. Start small and go up. 3, 6, 8, 10, and then 12mm. Clean up with 600 grit paper.

I just had an idea. I am going to bring in my plunger tomorrow to the office. I will measure it all up and make a paper template that can be printed out to add in spacing and placement.

any more details on this mod?  Possibly a picture or a drawing showing the finished item.