SAE50) or 20w50

cpg

Messages
12
Location
il
Great forum.I have a 1966 427 so. It has a mild build w/about 475hp. My cold idle oil presure is about 55. My hot oil pressure at idle is 20-30. Oil pressure at 3000+rpm hot is around 55-60. My question is since the car is only driven on nice 60deg+ days, could I use a sae50 vs a 20w50 oil?? The actual flow rate seems to be identical at room temp. I was thinkin of useing Kendall gt sae50....Thanks.
 

cpg

Thread starter
Messages
12
Location
il
Thanks for the WELCOME.I thought single weight out-performs the multi ? They floe the same at room temp out of a jar w/a small hole in it.?????? I'm just very curious.It is a old school engine .No hydrolic lifters.
 
Messages
18,449
Location
East of IGO
You are correct. Probably a 15w40 or straight 40 would give enough oil pressure when hot . I found 40 wts good in my BBC engines though I have used 50 wts
 

cpg

Thread starter
Messages
12
Location
il
OK, it looks like I will goin w/the 20-50,since no one has much to say about sae 50. What do you feel is the better ? BPenn,VR1,Kendall,Castrol..Dont need synthetic as I will change oil every 1k mi...It is a side oiler so it has a few leaks(small)but I heard syn. will make it worse plus for the amount I will change it I dont think its worth it...Thanks for the info guys.
 
Last edited:
Messages
1,267
Location
Tennessee
What it looks like coming out of a jar isn't as important as the technical specs. What if you lowered the room temperature 20 degrees, still think they'd look the same? I'll be one to say that I can't give a factual answer without seeing the data sheets. And that's what I recommend you do. Just google whatever oil you want to know about and add 'data sheet' to the search. Brings up the pour points, cst measurements, and more. It's likely that the straight 50 acts like a 20W-50. There are straight 30's than can also be labeled a 10W-30, so it's not unusual. With all that said, I would still go with the 20W-50 out of the two, because it's 2009 and multi-viscosity oils are not weak like they were 20-30+ years ago.
 

cpg

Thread starter
Messages
12
Location
il
I think for the amount I plan to change it and the 2-3000mi a year I will put on it the dino will be good. Somethin in the back of my head keeps tellin me kendal sae50....
 

cpg

Thread starter
Messages
12
Location
il
It is a ford 427 side oiler.W/7k miles. Oil pressure is around 25 when hot and 55-60 when cold at idle. 3000rpm pressure is 60 when hot. Oil temps run around 210-240 degree's. I just keep thinkin strait sae50 for summer. I dont mind leeting car warm up before I drive it.
 
Messages
43,674
Location
Ontario, Canada
Who built the engine? What do they recommend? Engine builder around here (does mostly GM stuff) seems to universally recommend a 15w40 or 5w40 HDEO.
 

cpg

Thread starter
Messages
12
Location
il
No, it was suggested to me bacause of my variance in oil pressure. 25-30hot idle and 55-60 at 3000rpm hot.Cold idle is 55-60.
 
Top