Oil Viscosity Recomendation

Status
Not open for further replies.
T

T_Bortz

Joined
Jun 29, 2016
Messages
23
Location
Pennsylvania
I have a freshly rebuilt engine with about 150 miles on it. Engine builder recommended 15w40 HDEO. I changed the oil a couple of times during break in. (Delo 400LE 15w40)

Oil pressure just seems way too high to me. 60ish psi at start-up and its been mid 80's here.

Oil pressure when warmed up seems to be a much more reasonable 25-30 psi at idle.

Would it be a smart move to switch to Rotella T6 5w40 or Mobil 1 0w40? I think the M1 may be too thin, but perhaps the T6 would give a more realistic oil pressure at startup?

Car is not driven when it gets below 45-50* outside. This is in a turbo car, 500ish bhp.

Any recommendations would be appreciated.

Thanks,
Tim
 
Last edited:
I would Run the T6 without question if you need the more robust add pack. It's a bit cheaper too which is a benefit.

I was in a similar situation when I rebuilt the L28et in my Datsun... Oil pressure was INSANE at cold idle with M1 15W-50. Running M1 0W-40 got my oil pressure in line across the board, in the winter and in the middle of the NC summer on the highway, with oil temps up to 220-240*F
 
Funny you should say that about 15-50. I tried M1 15w50 last night because a friend of mine had some. Holy oil pressure! It went up to about 70+ at startup!


I don't know if i necessary "need" the robust add pack, this engine has a roller cam, not flat tappets.
 
Originally Posted By: FordCapriDriver
What car , engine? What does the manufacturer reccomend?


Motor is freshly rebuilt with "looser tolerances". Like i said, engine builder suggested 15w40 HDEO.
 
Originally Posted By: T_Bortz
Originally Posted By: FordCapriDriver
What car , engine? What does the manufacturer reccomend?


Motor is freshly rebuilt with "looser tolerances". Like i said, engine builder suggested 15w40 HDEO.


For the 15th time, WHAT ENGINE, WHAT CAR??!!

How do you expect to get accurate advice if you cant even tell us what engine and what car? Is it s 2014 Honda Civic? A 1970 Hemi Cuda? A 1926 Model T? Is it a 24 foot airboat?

What are you going to do with it? Is it a race car? Is it a Sunday driver? Just taking it to car shows? Is it a circle track car? Is it a drag car? Is it a daily driver?
 
Originally Posted By: T_Bortz
Sorry...

85 Merkur XR4Ti
2.3L Turbo
Roller Cam
Rebuilt with "looser than stock" tolerances


15w40 sounds good...
 
Ooooh nice A.k.a the Ford Sierra over here in Europe, i think M1 0w40 would be fine for it maybe even Mobil 1 Racing 4T 10W-40? , when the engine is running cold pressure is not really what you have to worry about, it's flow specially in a OHC Engine and one with a Turbo... please post pics
smile.gif
 
Originally Posted By: T_Bortz
I have a freshly rebuilt engine with about 150 miles on it. Engine builder recommended 15w40 HDEO. I changed the oil a couple of times during break in. (Delo 400LE 15w40)

Oil pressure just seems way too high to me. 60ish psi at start-up and its been mid 80's here.

Oil pressure when warmed up seems to be a much more reasonable 25-30 psi at idle.

Would it be a smart move to switch to Rotella T6 5w40 or Mobil 1 0w40? I think the M1 may be too thin, but perhaps the T6 would give a more realistic oil pressure at startup?

Car is not driven when it gets below 45-50* outside. This is in a turbo car, 500ish bhp.

Any recommendations would be appreciated.

Thanks,
Tim
What do you mean the oil pressure is too high? Realistic pressure on start up? I hope you didn't read Oil 101 and now think you know something more than the engine builder. What only matters is the hot oil pressures. The oil is too thick upon start up is when there is no or low oil pressure.
 
M1 15w-50 +1, Turbo motor = heat. hot idle pressure 20-30 and when it revs up 50-70 sounds like a good long life to me.

I remember around Detroit those cars were not numerous and very quickly I stopped seeing them. Which tells me the powerplant was not typically long lived.
 
Originally Posted By: CT8

What do you mean the oil pressure is too high? Realistic pressure on start up? I hope you didn't read Oil 101 and now think you know something more than the engine builder. What only matters is the hot oil pressures. The oil is too thick upon start up is when there is no or low oil pressure.
[/quote]

60-70 psi @ startup seems excessive to me. I never read Oil 101, but i guess i shouldn't. Most wear is at startup, with 60-70psi i couldn't imagine it would even turn over when it starts getting cool out.

And yes, i do think i know more than my engine builder. Since i had to fix multiple mistakes of his. But that isn't the point here.
 
Last edited:
Originally Posted By: Joshua_Skinner
If you want lower peak oil pressure then put a lighter relief spring in the oil pump.


I never said i wanted lower peak pressure. It just shouldn't need to have max pressure at idle.
 
Originally Posted By: Joshua_Skinner
If you want lower peak oil pressure then put a lighter relief spring in the oil pump.
NO000000000000000000000000000000001
 
Originally Posted By: T_Bortz
Originally Posted By: CT8

What do you mean the oil pressure is too high? Realistic pressure on start up? I hope you didn't read Oil 101 and now think you know something more than the engine builder. What only matters is the hot oil pressures. The oil is too thick upon start up is when there is no or low oil pressure.


60-70 psi @ startup seems excessive to me. I never read Oil 101, but i guess i shouldn't. Most wear is at startup, with 60-70psi i couldn't imagine it would even turn over when it starts getting cool out.

And yes, i do think i know more than my engine builder. Since i had to fix multiple mistakes of his. But that isn't the point here. [/quote]most wear from start up is for the metal being cold .The clearances of the piston cyl wall are the max because pistons are oval ,measure them looser = more wear and blow by. then the condensation at the cyl walls etc [hot combustion and cold metal] ,then there is the richer air fuel mixture to keep the engine running when cold all combine which washes the oil film Now if is 20*f below zero and there is straight 30 wt in the crankcase the oil will not travel to the pump there will no oil pumped to lube the engine That is 0 oil pressure. In most circumstances the remaining film is enough to lube the engine when the proper viscosity oil is used to lube the enginge until the oil reaches the parts. As mentioned hot pressure is the only pressure that really means something. and the proper viscosity is used for the starting temps. It is good you didn't read oil 101 .
 
Makes sense that not all startup wear is oil/bearing related.

However, is 60psi at startup not excessive? Is there really any reason NOT to try a 0w40 or 5w40 if warmed up oil pressure is all that matters?
 
Originally Posted By: T_Bortz
However, is 60psi at startup not excessive? Is there really any reason NOT to try a 0w40 or 5w40 if warmed up oil pressure is all that matters?


There is no reason not to, no. But it is going to depend on the starting temperature whether there is any difference. There's no guarantee a 5W or a 0W oil is going to be any thinner at startup than a 15W. It all as to do with the temperature.
 
Status
Not open for further replies.

Similar threads

Sweebation
What oil to use in 2005 6spd corvette
Replies
17
Views
619
twX
D
LS1 Lifters and Oil Viscosity
2
Replies
21
Views
800
ZeeOSix
SubZero350
Detergent or Non Detergent oil? 1954 Chevy 235 inline-6
2 3
Replies
47
Views
4K
Brons2
A
1989 Isuzu Trooper oil with high mileage
Replies
11
Views
692
Alexis
0
Good 50wt oil ?
Replies
16
Views
650
FCD
Back
Top