Fellers, I have a 350 SBC in my Model A, runs quiet and smooth. Runs strong even though it's a stock engine. When the engine is cold, it runs 45-50 lbs of oil pressure. Gets hot, at idle, it drops to probably 8-10 lbs. Hot at cruising speed, it's about 35 lbs. It doesn't make any noise and runs great. I just like a bit more oil pressure. Any experienced guesses? Bearing clearance too much? Oil pump weak? I've always heard 10 lbs at idle is sufficient but still don't like it! Jackie
As the technicians will say "That is within spec, what's the problem?" Those numbers sound fine to me, any idea on the history of your motor? If the pressure is lower than it has been, the first place I go on an SBC is cam bearings... Disclaimer...If Squirrel chimes in and says ANYTHING different than I said, go with his info!!!
I have no idea of the engine's history. I've had it a few weeks, just took the fenders off in the pic. It is the same since I've had it though. I am going to change the cam in a few days and will put new bearings in. I'll put in a new oil pump also. I jsut like a little more pressure at idle. Thanks.
Its within specs .Guage is probably off.My poncho reads 0 at idle and swings up when driven ,I figure it was the guage or it would be tapping after 15 minutes idling.............
What oil do you run? You could try a 40 or 50 racing oil to see if it helps. I always like the high volume pumps to keep pressure up at idle.
It has 20W40 Castrol in it now. I guess I just shouldn't be concerned about it. Just like oil pressure at idle. BTW, the hood, fenders, and running boards are for sale.
I have the same problem with the car I just bought I've givin up on it Im just gonna be rebuilding the motor.
I run Rotella or Delo diesel oil in all my flat-tappett engines. Not sure whether your motor is a roller or not, but your oil pressure is in the ballpark for sure.
Thanks! It;s just a stock "010" block 350. I'll just live with it and drive happily. She sure drives good.
I have a stock 350 that has done that at idle for many years with no noise or ill effects. I will worry when it starts making noise.
Electric sending unit or mechanical? The gauge it self may not be accurate. Also the location that you are picking up the oil pressure from can make a difference.
Put a simple mechanical gauge into the spot where the sender goes and see what it reads. Dash gauges are notoriously off. BTW, off topic, but that thing looked *****in with the fenders. I'm not normally a fender guy, but the car just looked so right. Don
I've had a lot of cars through the years that had low oil pressure at idle when hot. Never had a problem with any of them. Had a Ford that would drop to zero on the gauge at 600rpm, but run 25psi at 675rpm at idle, so I just set the idle up and forgot about it. As Don mentioned, I'd at least hook up a temporary mechanical gauge to it to find out for sure.
its 10 PSI for every 1000 RPM you run........If I have to question the oil pressure, I will use another gauge. Try 20W50 Rotella
YUP x2 10psi for every 1000 rpms and 20/50 is a must in small blocks, they love thick oil especially in the valve guide areas. For a streeter this is well within specs. Drive it!
To replace the cam bearings you will have to take the engine apart down to the bare block. They press in and you need to set the center bearings in place through the crankcase. I say drive the **** out of it and put those fenders back on. It looked *****in with fenders!!
Thanks Fellers, I'll go to the 20W50 Rotella. I like it anyway because it has Zinc in it. I'm just gonna drive it! Probably without the fenders. LOL
I'd go with a straight 50 weight. It doesn't get very cold in Tennessee and you wouldn't drive the car if it was cold out. You don't need a multi-viscosity oil.
As long as it meets the 10# of pressure for every 1000 rpm criteria there's no problem. I'd like to have the money SBC owners have spent over the years to "correct" what they consider to be low oil pressure. BTW flow is more important then pressure. Back in the day all we did was stretch the oil pump spring to raise the pressure. I had a 283 that you could peg the oil pressure gauge on hard acceleration. When adjusting the solid lifters it would pump oil all over the fender wells. When you don't know any better, you do stupid things. Why would you use high viscosity oil just to raise the oil pressure? Just stretch the spring, it makes just as much sense. Drive the wheels off it and don't spend any time or money on a problem that doesn't exist. Why remove the fenders off a great looking car?
The 350 in my 38 Chevy had 8 lbs hot idle and barely 20 lbs hot/freeway speeds for about 2 yrs. I finally got off my lazy *** and put a high volume pump in it (bearing clearance was fair). Now it's got 15 lbs at a very HOT idle....but, more important, when it's under a load at freeway speeds and hot it now has 50 lbs. BTW, it's been my experience that changing oil weight only affects cold oil pressure. They all seem the same on the gauge once up to temp after a few miles at freeway speeds
Just drive, You've got more oil pressure, gage off or not, than my SBF and it runs like a striped-***ed ape! Some of these guys would tear down a brand new car soon they got it home. If it ain't broke drive the **** outa it! My SBF has less oil pressure, doesn't use any oil and doesn't smoke. I'd jump in it and head for Cal. if it had A/C! Are you sure you wanna sell the hood and fenders? Even if you don't run 'em now, stash 'em, or you'll more'n likely regret it, unless you need the money? Congrats, it's a neat ride. Oh, I use straight 30 HD engine oil year round.
Had a 54 Chevy pu when I was a teenager with a 283 that would drop to below 10 psi at idle....got all freaked out about it, but was told by my dad and his friends not to worry about it. I ran it like that with no issues until my brother totaled it. The thing had a two speed aluminum powerglide in it that I pulled out of a near perfect 66 or 67 Chevy station wagon. (we put a junk transmission in the station wagon to get it going again and rode around in it in farm fields....jumped ditches in it, etc....just beat the living hell out it. It kinda makes me sick now, but in 1985, it was just a stupid old station wagon) After my dumb*** brother killed the truck, one of my dad's drag racing buddies bought the transmission from me for his race car. Anyway...didn't mean to hijack the thread....but these random car memories come back to me from time to time. It seems like most of the fun I had as a kid involved cars in one way or another.
It used to have the zinc, bit if you do a search on here you'll find out otherwise. Oh, and replace the fenders and boards. The lowered (un-mounted) headlights gives the impression that the coupe sadly misses them.
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