I have pulled my 327 out of my '73 and am doing a few things. However, I am running into the "replace everything while you're doing it" syndrome. I don't want this little detailing project costing me $$$$$$$$$$$$.

Before pulling, my aftermarket oil pressure gauge read about 40 psi at idle and 80-90 psi on hard acceleration. I am replacing the oil pan gasket.

Any reason I would want to get a new oil pump at this time? I guess my concern is that I don't know how old it is and as long as I have the pan off...

Any advice?

Replace it if you don't know the history on it.It is a cheap investment the way I look at it.

I replaced mine when I first got my camaro. Since there older cars, they were fast, and muscle cars, most people that had them before you just gunned the living ___ out of them and then get bored of them. That is what I have learned recently after going and looking at about five camaros in the last week. If you can afford it, and dont want problems later, replace it while your in that area of the car.

seems to be making way plenty pressure. i really wouldn't spend the money on it. maybe an upgrade to the steel sleeve'd intermediate shaft/drive rod though. if it doesn't have one,, that would be a must with the high pressure output,,like it seems that you have. 80-90# is up there. jmo.

you should be okay with that pump remember the way it's rated for pressure is 10lbs pressure for every 1000rpm

The oil pressure on that pump was set way too high. Idle pressue is not in the spec of any Chevy products. All oil pressure specs are at 1500 rpms and are usually 35 psi there. The idiot lite pressure sensor comes on at somewhere around 3 psi so you could say that the idle oil pressure should be above 3 psi.

Grumpy Jenkins says that with any oil pressure over 50 to 55 psi the oil pump will cavitate--not a good thing. He also goes on to say that the oil pump pickup should be set at 3/8" to 1/2" off the bottom of the pan (and this is critical). The oil pump pickup should be eithera brazed, welded, or a bracket (like this: http://www.jegs.com/webapp/wcs/stores/servlet/product2_10001_10002_751362_-1n ) should be used to keep it in place and at the right height.

seems to be making way plenty pressure. i really wouldn't spend the money on it. maybe an upgrade to the steel sleeve'd intermediate shaft/drive rod though. if it doesn't have one,, that would be a must with the high pressure output,,like it seems that you have. 80-90# is up there. jmo.


I don't have it apart, but I was going to make sure I had the steel sleeve/shaft. Thanks

Cardinal...you got me a little worried.

is 80-90 psi really too much pressure? If so, does that mean I NEED to replace the pump that's in there now?

Although I have not gone through the engine yet ('66 Corvette 327 with 2.02 fuelie heads), the previous owner (an honest guy that I TOTALLY believe) told me it has been built up... 10.5 to 1 speed pro forged pistons, etc... I assume this would come into the equation.

Maybe 80-90 psi would be too much for stock but mine is certainly not stock.

Sounds like 80-90 psi is HIGH...could my gauge be giving me a faulty reading? It looks to be working fine because it shows idle pressure and goes up as the pedal is gassed.

Thanks in advance.

like muscl car said,, all that's really needed is about 10#'s for each 1000 rpms. and some say that's overkill. but it's been the basic rule of thumb for years. if it revs to 5500,, then 55#'s as an example. there's lots of guys here running more rpms with the standard volume/standard pressure pump with no problems. maybe they'll speak up.

with more pressure,, it's a little bit harder on cam gears/distributor drive gears/oil filters and reduces horsepower output slightly from turning the pump against the added resistance of the higher pressure output. once you get to about 95-100#'s,, start keeping an eye on those budget oil filter housings at the rolled seam seal. hope it helps.

are you sure your oil pressure gauge is correct. that's alot of pressure. I'd check the accuracy of your gauge first..

With the quality of some pumps available these days I would keep what already works.

once you get to about 95-100#'s,, start keeping an eye on those budget oil filter housings at the rolled seam seal. hope it helps.

thanks. I have the canister-type oil filter ('66 engine)...not the scew in type, so that won't be an issue.

are you sure your oil pressure gauge is correct. that's alot of pressure. I'd check the accuracy of your gauge first..

I've been thinking that. How do I check if the gauge is accurate?

Also, there is air in the line, but read on here that pressure is pressure and you don't have to bleed the oil pressure gauge line for it to be accurate...true?

With the quality of some pumps available these days I would keep what already works.

if it ain't broke...

if it ain't broke...

ditto,, from the beginning. at least it's not too low of a pressure you're seeing. always rather see it a tad on the higher side in my opinion.

to be honest, I don't have the slightest idea on how to calibrate them gauges, or if they can be. Mine was showing 50 psi at idle, I knew it couldn't be right, so I went and got a new one and hooked it up and it read about 10 at idle.

Alright dont laugh, heres what I did to make sure mine was right... I went to walmart, got a oil gauge by itself, set it all up, set it down so it woudlnt go anywhere, then had my pops check the gauge as the car was on and i reved it... there like 10 bucks too lol. Just a idea.