Author Topic: Approximish spacers needed to increase oil pressure?  (Read 615 times)

Offline Turbodave

Approximish spacers needed to increase oil pressure?
« on: June 04, 2018, 10:20:36 PM »
Iím using the ball & spring, and seem to be maxing out at 50psi cold, which ends up at 25psi when piping hot. I think itís time to put a little more pressure in the old girl. Is there an approx spacer/psi relationship, or can I work on assumption of if I have (for example) 0.5Ē of spring compression and have 50psi then 0.6Ē of compression (0.1Ē spacer) will give approx 10psi more? (This seems to make sense)...
I donít mind trial and error, but if someone has been there before, and knows the answer, Iíd appreciate it.

Cheers!

Online MiniDave

Re: Approximish spacers needed to increase oil pressure?
« Reply #1 on: June 04, 2018, 10:37:39 PM »
I had the opposite problem anytime I used the ball and spring set up, it pegged my oil pressure gauge at 100 psi, I tired cutting off one coil but it didn't make any difference so I gave it up.

No idea if it's a linear pressure with the length of the spring, I'd say put in the spacer and see what happens.....keep adding till you're happy. But I think I would try the stock spring and plunger to see what pressure you get with them first. When I couldn't get the ball to work I put a new plunger and spring in mine and it cured my low pressure readings.

Is your 50lbs at 3K rpm or idle?
1989 Cooper Racing Green
2009 Clubman S
1969 Jaguar XK-E FHC
2004 Audi Allroad 2.7 TT

Offline jedduh01

Re: Approximish spacers needed to increase oil pressure?
« Reply #2 on: June 05, 2018, 09:35:47 AM »
I would consider jumping straight to a directly adjustable unit. 
 To me the back and forth on the 'shims would drive me nuts!


https://www.7ent.com/products/oil-relief-valve-adjustable-for014.html 

also can ' drill + tap + make your own...


Offline croc7

Re: Approximish spacers needed to increase oil pressure?
« Reply #3 on: June 05, 2018, 01:43:37 PM »
I've read that use of the ball could deform the plunger seat and cause oil pressure fluctuation.  Others have said they've used the ball and spring for years with no trouble, so the choice would be yours.  I stayed with the plunger and spring.  To raise oil pressure, compress the spring by placing an appropriate size washer inside the domed oil pressure nut.  Or buy a new plunger, lapping it in the seat and install a Cooper S spring which is rated at 70 PSI.  If the result is oil pressure that is too high, install a copper washer/s between the domed nut and the engine block to effectively lengthen the spring.  Good luck.  Let us know the results.
« Last Edit: June 08, 2018, 06:57:50 PM by croc7 »

Online MiniDave

Re: Approximish spacers needed to increase oil pressure?
« Reply #4 on: June 05, 2018, 03:37:52 PM »
I found those adjustable oil pressure thingies to be of less than stellar quality, I'd go with Croc's recommendations. But, I wonder if the issue is a worn engine rather than a weak spring - that's why I went with a new spring and plunger - to be sure.....my results were good fortunately.
1989 Cooper Racing Green
2009 Clubman S
1969 Jaguar XK-E FHC
2004 Audi Allroad 2.7 TT

Offline Turbodave

Re: Approximish spacers needed to increase oil pressure?
« Reply #5 on: June 06, 2018, 01:23:34 PM »
Canít use adjustable unit as I have an intercooler pipe about 3/8Ē forward of standard cap.
This is also why I was wondering if anyone had real life experiences of the spring force/displacement as itís a royal PITA to get in there. Iíll baseline my current spring force at seating, spring compression at seating, spring rate, and the oil pressure attained, and then do a few tests to correlate the math for an increased spring force.

« Last Edit: June 06, 2018, 03:10:19 PM by Turbodave »

Offline croc7

Re: Approximish spacers needed to increase oil pressure?
« Reply #6 on: June 08, 2018, 06:29:50 PM »
I looked at my notes from a couple of years ago when I was fiddling with high oil pressure and shortening the free length of the spring by 0.1" = 10#s pressure drop.  Don't know if the inverse is true.  And with a stated clearance 3/8" of between the dome nut and an inter-cooler pipe on your engine, I don't think that the adjustable oil pressure valve would fit-the knurled adjustment knob of the valve would interfere with the inter cooler pipe.
« Last Edit: June 08, 2018, 07:00:33 PM by croc7 »

Online MiniDave

Re: Approximish spacers needed to increase oil pressure?
« Reply #7 on: June 08, 2018, 07:49:05 PM »
Croc, I took one coil off the spring when I was trying to get the ball style pressure regulator to work, still showed 100 psi or more cold (my gauge was pegged)

That's when I decided to go back to the stock spring and plunger. Mine now shows 70 cold, 60 hot at 2500 rpm and above.
1989 Cooper Racing Green
2009 Clubman S
1969 Jaguar XK-E FHC
2004 Audi Allroad 2.7 TT

Offline croc7

Re: Approximish spacers needed to increase oil pressure?
« Reply #8 on: June 11, 2018, 12:06:25 AM »
I had oil seeping/leaking/oozing/weeping from the lock nut threads of my adjustable oil pressure thingy.  Solved it by sealing the threads with the Toyota product FIPG.

Offline Turbodave

Re: Approximish spacers needed to increase oil pressure?
« Reply #9 on: June 11, 2018, 02:11:51 PM »
Well, I figured I give you guys an update.

I pulled the spring out of my engine, and realised it had a plunger in there, not a ball. I built the engine less than 11 months ago and Iíd completely forgotten.
Looking through my past build notes,  I actually got rid of the ball many years ago because of the weird fluctuating pressure ( thatís what my notes say at least ).
Luckily I have a stockpile of stock engines, so went and pulled a spring from one of them, and at some point, I obviously shortened the spring as my original spring was 1/2Ē shorter than another A+ spring.
 I just went ahead and put the stock A+ spring in my engine, and got 60psi immediately.  I couldnít run it up to temperature because I didnít have any coolant in it at the time, but Iíll report back.

Offline croc7

Re: Approximish spacers needed to increase oil pressure?
« Reply #10 on: July 04, 2018, 12:14:37 PM »
Were you able to solve your low oil pressure problem?

Offline Turbodave

Re: Approximish spacers needed to increase oil pressure?
« Reply #11 on: July 12, 2018, 05:13:54 PM »
Well yes!
The factory plunger and factory (used) spring provides 50psi cold (or as cold can be expected at this time of year!) and 35 psi when super hot (as can be expected at this time of year) at 950 rpm. Remember though that although Iím running the ďhigh capacityĒ turbo pump, Iím feeding the 16v head (that needs more volume flow than the rocker shaft of the 5-port), the turbo, and the piston cooling jets - all of which consume valuable oil flow at the low RPMs.