Oil pressure question.

-

Darren

FABO Gold Member
FABO Gold Member
Joined
Mar 1, 2006
Messages
1,584
Reaction score
690
Location
ontario
Hey guys
I am running a 68 383 recently rebuild with std volume oil pump, running 10w30 with a Wix filter. My oil pressure warm is 13ish PSI, is there something I could do to increase PSI to say 20 warm?
Thanks for any advice.
 
What are your bearing clearances and where is the oil going? Is there a plug missing? That’s low unless you are running 20w50 sized bearing clearances.
 
Have you verified the gauge is accurate against another gauge or another sending unit? If you’re using electric gauges you can contrast with a mechanical gauge if you have one. Also I have seen guys replace a weakened oil pump spring with a new one or even add a washer to help stiffen the spring and get improved pressure. I get low 20s for pressure, warm and idling on my 383 in my Roadrunner.
 
What are your bearing clearances and where is the oil going? Is there a plug missing? That’s low unless you are running 20w50 sized bearing clearances.
Not quite sure clearances.. I got the short block build from a builder that is no longer in business..
 
Have you verified the gauge is accurate against another gauge or another sending unit? If you’re using electric gauges you can contrast with a mechanical gauge if you have one. Also I have seen guys replace a weakened oil pump spring with a new one or even add a washer to help stiffen the spring and get improved pressure. I get low 20s for pressure, warm and idling on my 383 in my Roadrunner.
I'm running a aftermarket oil gauge, I do have a Autometer I'll be confirming pressure in next few days.
Thanks
 
I was always taught the general rule of thumb is 10psi for every 1000 rpm to keep that engine sufficiently lubricated.
 
Reading your other post, regarding valve clearance, You stated that you're using Comp 911-16's, These go in at 1.900/ 122lbs to 1.850/141 lbs. I'm gona ask NO click/tick when engine is cold? I watched the video. Low oil pressure when engine is warm? 10-12 or 13 lbs at idle aint gona cut it at keeping a hydraulic lifter filled with that kinda seat pressure. Especially with a 1 size fits all lifter program from Comp. SBM and BBM lifters kinda aren't the same.
20220810_090122.jpg

20220810_090353.jpg
 
Reading your other post, regarding valve clearance, You stated that you're using Comp 911-16's, These go in at 1.900/ 122lbs to 1.850/141 lbs. I'm gona ask NO click/tick when engine is cold? I watched the video. Low oil pressure when engine is warm? 10-12 or 13 lbs at idle aint gona cut it at keeping a hydraulic lifter filled with that kinda seat pressure. Especially with a 1 size fits all lifter program from Comp. SBM and BBM lifters kinda aren't the same.
View attachment 1715970033
View attachment 1715970031
Yes.. cold I got aprox 40 PSI at idle, I'm pleased with how smooth engine runs, as it warms up to operating temperature I'm at aprox 13 PSI warm at idle, I get the tick/ clack from I'm assuming lifters, I did readjust the preload lastnight on drivers side bank to 1/2 turn. Didn't seam to make much difference.
 
But u still decent pressure at idle to lube the bearings, cam and lifters. If pressure is less than 25 psi at warm I’m worried. Kim
I agree. If I was 25 PSI warm at idle I think I'd be pleased.. I think Max is onto something concerning my combo.
Thanks
 
Last edited:
Good luck with the fix on that! Sounds like you’re in good hands Darren! I’m new to interacting on here and just trying to be helpful. Wasn’t aware that was potentially that in depth. A bit out of my wheelhouse at this point. Maybe one day I’ll have something a bit more useful for ya. - Nick
 
A most important question has not been asked!
What is the idle rpm? If 500 rpm, 13 psi is ok. If the idle rpm is 1100 rpm, then 13 psi is probably a bit low. Thicker oil & NON friction modified oil are two things that would increase pressure slightly.
 
Most factory service manuals give oil pressure spec above idle. What does the pressure do AS SOON AS you blip the throttle? Where is the pressure at say, 1500 RPM?
 
A most important question has not been asked!
What is the idle rpm? If 500 rpm, 13 psi is ok. If the idle rpm is 1100 rpm, then 13 psi is probably a bit low. Thicker oil & NON friction modified oil are two things that would increase pressure slightly.
It's a 4 speed I have the factory tach, idle is around 1000 rpm thanks
 
Most factory service manuals give oil pressure spec above idle. What does the pressure do AS SOON AS you blip the throttle? Where is the pressure at say, 1500 RPM?
I will check that out today..
Thanks
 
I'm going to try to upload a video of cold and warm clip.
Thanks for the advice
 
Is this a stock or HV oil pump? I'm not sure I'd worry either way. This 71 Chevy truck I've been working on has an HV pump. Cold idle oil pressure is over 50. I can make it hit 80 plus revving to like 3500 cold. When it's hot and idling, it's under 20. AS SOON AS the gas pedal sees the weight of a big toe, the pressure jumps to 40 hot at around 1200 rpm. 60 hot at about 2500 rpm. Do what you want with it, but IMO I think it's fine.
 
Is this a stock or HV oil pump? I'm not sure I'd worry either way. This 71 Chevy truck I've been working on has an HV pump. Cold idle oil pressure is over 50. I can make it hit 80 plus revving to like 3500 cold. When it's hot and idling, it's under 20. AS SOON AS the gas pedal sees the weight of a big toe, the pressure jumps to 40 hot at around 1200 rpm. 60 hot at about 2500 rpm. Do what you want with it, but IMO I think it's fine.
It is a std ( new) volume oil pump.
 
-
Back
Top