OK well I just changed the oil on my 92 camaro rs with a 305 tbi yesterday to mobil 1. Fired her up, everything was fine and I go to take her out for a spin and decide to run her though the gears and I'm paying close attention to the oil pressure while doing this. The oil pressure is reading about 45 psi at full throttle and when i hit 4500 rpm it start to drop below 30 psi and as soon as I shift it goes back up to 45. What could be causing this?

 

factory gauge?...sounds like a bearing issue to me...weak oil pump..sending unit on pressure gauge...to name a couple..

 

Sounds like all the oil was in the valve covers at higher RPMs.

Don't run your motor that way, it's not long for the world with no oil in the pan for the pump to pump. No big deal though, if it's a stock L03, it doesn't make power up there (that is, the car will go faster if you shift before it gets there), so there's no need for it.

Weak valve springs will cause that, by letting the valve train have slack in it, which will greatly increase oil flow to places it doesn't need to go.

 

What do you mean by bearing issue? Yes it's the stock guage, but before the oil change it never did that before. Could it have anything to do with the distributor going bad because I know I need to replace it before it completely conks out.

 

RB just confused me a bit....RB are saying you shouldnt turn a 305 to 4500 rpm???.....

 

No, nor any other motor either.... not when it has no oil pressure. That's what the gauge is telling you, it's the car's way of saying "STOP, driver!!! You're killing me!!!!".

Put some new springs in it, it should do a whole lot better. Even if it doesn't fix the oil pressure thing (which I suspect it will), the enigne will run a whole lot better, especially at high RPMs.

 

ok, I see what you are saying now...I agree there is a problem somewhere .and yes , he shouldnt drive it in the state its in..without oil pressure he is asking for disaster! Oil pressure should increase with RPM. If it decreases...serious **** going on. RB is much more qulified than myself to advise you on this.