Inliners International Forums General Discussion Engines 292 Oil Pressures ?

Recently installed oil pressure gague on my 64 Chevelle 292 with a 250 integral head and a Rochester 2 barrel on top. Motor runs strong.It has been hard to find a chart or specifics for what is correct for the pressure to be reading at idle and at say 55 mph. That info is not in my Haynes manual nor is it in my 64 Chevelle shop manual for the 194.So I now ask the pros at Inliners. Thank you.

What RPM are you turning at 55 MPH, and what pressure do you have at that speed and at idle.

Idle is 6 psi when engine is hot and about 25 or 30 psi at 60 mph. Do not have a tach. Now where is the answer from some engine builders ?

20 psi would be good for hot temp idle, 40 to 45+ psi for highway speed. Oil pump type and overall engine condition will affect that also.

I've got 80K miles on my 292. It has almost 30psi at hot idle and 45 underway.

That oil pressure is low. What oil are you running? I would expect 20-30 idle and 35-45 highway. Tom

Yes, I thought it was too low. Oil used is Rotella conventional 10w-30 with a GM Cam break for the high ZDDP. 292 is rebuilt with about 15,000 miles. Oil pump was either from a rebuilt kit or bought from my local engine builder. It is not a hi-volume pump. So what are ideas for fixes ? Thank you guys for the comparisions.

1st, try another gauge.
Next, increase the viscosity to like 10W40, get the temperatures to match and see what the pressure does.
If it goes up, the pump gear end play may be loose (over .003") or too much gasket thickness between the body and cover, but the relief valve is OK. If this oil is good for you (cranking speed is fine, pressure goes up instantly when started) I'd feel good leaving it.
If it doesn't go up, try even higher like 20W50 or straight 40 (no hard throttle until it's warm). Same deal - if it goes up, either the pump or bearings are loose. That oil isn't really a great choice for all-around.
No pressure increase means the relief valve is blowing off too low - bad spring, leaking relief piston. This means the pump has to come out.

It's a good idea to bench test your oil pump. This can be done by attaching a pressure gage to the outlet, submersing the pickup in a pan of oil, and spinning the shaft with a drill motor. I drill and tap NPT but I'm sure other methods can work. This will flush out a new pump and also can be used to check pressure relief function.