hypoluxa

What pressure are you seeing? I've seen a difference of upto 3 bar at idle, some designed that way, some not

Pressure at cold start, warm idle, 3k, 5k, and 7k would be nice oil type and MY.

Particulary interested in those who have had a rebuild or a shimmed pump.

Cheers.

StanS

iTrader: (3)

UK98 silkolene S
Reshimmed - cold tick over 100psi, gentle revs 100+
hot tickover 60-65psi runs @95psi
(Can't be bothered to divide by 14.7 for bar !)
Stan

[Edited by StanS - 1/13/2003 7:35:50 PM]

hypoluxa

That'll be a Town End rebuild then Stan?

Whats the maximum pressure you see apart from a cold start?

swan

Cold - 6 bar
Warm idle - normally around 2 bar if I haven't been pushing it, else upto 4 bar.
As for at the various rpm's - too busy watching the road/revs. Have yet to see it go over 6 though.
MY01

[Edited by swan - 1/15/2003 1:47:18 PM]

StanS

iTrader: (3)

Hypo
95psi is max I've noticed.
Stan

Bob Rawle

Idle hot 4.8 bar, anything over 1800 rpm 6.5-6.8 bar. RCM oil pump. Cold pressure on starting is 7.5 bar. Motul M300V 15-50, STi5 (sort of)

hypoluxa

Bob,

Have you had a rebuild? That pressure surely can't be down to just the modified pump?

I've looked at a Prodrive Group N car which ran 1bar at hot idle.? I presume they run bigger clearances, which amongst other things would drop the pressure, but 1 bar does seem very low. The engine was new btw

Be interesting if anyone has any data for any of the high powered Jap/Oz cars...

Bob Rawle

Yes I've had a rebuild ... pressure is about 1 bar lower if I don't use Motul on idle but the same everywhere else, agree its pretty damn good, testiment to the rebuild. I am using a STi 7 block although I can't believe that makes the difference. Oil pump is the normal RCM modification. When I ran my std engine pressure was 3.4 bar idle and 6 bar from 1800 up using Motul. Running with Shell Helix Ultra idle pressure was 2.4 bar.

hypoluxa

Did you specify that pressure Bob, or the builders?

I was under the impression that the RC mod on the Oil pump was to shim the relief spring? As yet I haven't come across anyone who has changed the actual 'gearing' on the pump.

I think Motul must be French for treacle

Bob Rawle

No the spring is not shimmed afaik but the plunger is modded to prevent stiction and pickup, Motul has a superb viscocity index which is why I stick to it, also the engine was blueprinted and the clearances are spot on. I have to say I was very impressed with it indeed.

hypoluxa

Certainly agree regarding modding the plunger. I recently dissmantled a pump to find the plunger was scored badly down one side, made a horrible grating noise if you rotated it in its bore. This particular pump had been shimmed around 6mm, and the way it had been done left a lot to be desired to say the least. The engine connected to it had to be rebuilt, partly due to oil problems.

IIRC the opening pressure for the relief valve is around 5bar, with your pressures being higher I would imagine that your pump has been shimmed.

What are your oil temps like?

harvey

iTrader: (48)

STi ver 6 31000mls and RCMS rebuild at 14500approx.
Motul 300V 15-50. Runs at just over 90 psi hot in the cruise at 4000 rpm (96mph). 55-65psi tick over.Have noticed this oil runs around 5psi higher than the equivalent other makes I have tried and oil temp also appears to be marginally higher. Have also noticed that on all oils, the pressure is slightly higher immediately after an oil change for a few hundred miles and then settles on a value that is maintained to the next change.As we speak Roger Clark Motorsport are changing the oil to their Silkolene brand along with other work and I will be monitoring performance for them.

chiark

I've noticed increased hot idle pressure using motul 15W50 too - glad to know it's nothing out of the ordinary...

Adam M

Bob, with regard to oil,

have a read of this thread. This guy mycroft works in the oil refining industry and has a massive interest in cars as well as a fantastic fundamental understanding of engines.

Have to say I am not so interested in oils, and would rather someone else just told me what to use use which is probably why I have ended up running motul. But he takes an active interest and knows far more technically which oils to use and why. Was just wondering if you might be able to decypher what it is he is actually looking for in an oil and see if motul or anything else available fits his bill.