verbs

I think my oil pump is about to crap out on me....I just happened to be looking at my oil pressure gauge while testing out my new LCA relocation brackets and subframe connectors.

During a couple first gear WOT runs, oil pressure was holding solid until about 5000rpms at 65-70psi, but then after 5000rpms, the oil pressure plummeted to as low as 35-40 psi at 6500rpms or so!

The odd thing was, that after shifting into second and running it up to 6500rpms or so again, the oil pressure held fine at 70psi.

Only when I did WOT runs in first gear did I have this problem. I tested it out in a few other gears and no problems.

Maybe it was a coincidence, I don't know, but I know my oil pressure gauge shouldn't be plummeting in any gear, and I don't know why its only doing it in first gear WOT runs. It only plummeted 2 or 3 times total, but I think that's a sign of things to come.

Jantzer98SS

iTrader: (54)

Check your oil level. Mine does the same thing when it's low on oil. Except I never get close to 70psi, maybe 45-50 at the most. Sometimes 20psi at idle.

The Emperor Of Darkness

20PSI at idle?!?!?!?!
why is that???

it happened to me and now I found out that I need to replace the Crank bearings

verbs

Yeah, my oil pump has been a champ!!

SOB you were absolutely right....thanks! Sure enough the car was low on oil. Now I gotta figure out why the car is eating oil. Hasn't eaten any oil since I got my rings replaces with GM's TSB a few years back. Now for some reason its eating oil. Its not leaking, that's for sure, I just gotta figure out where the hell it's going!! Any suggestions?

cantdrv65

iTrader: (3)

Mine does the exact same thing when 1 1/2 to 2 qts low on oil.....

Jabroni

Don't worry! All your missing oil is in your intake, PCV system and intake runners in the heads!! Mystery solved!

If it's not eating a whole crap load of oil, I wouldn't worry about it. Just monitor the level regularly.

StrongWS6

Thanks Verbs and Chris. Just today I noticed that in first gear, didn't think twice about it till now. Going to check my oil level.

verbs

I am worried; my car hasn't eaten oil for the last 25,000 miles until just recently.....I got the bad rings replaced via GMs TSB a while back and hadn't had any oil consumption problems up until just recently.

NicD

iTrader: (7)

Ahh, my car does that as well when I am a quart or two low.

As for the oil usage issue, that might have to do with the 7000 rpm limiter you have had lately with your heads/cam setup. You may have hurt/worn some things in the bottom end like bearings, rings, etc.

Welcome to my world of oil consumption.

StrongWS6

All I did was add a 1/2 quart of oil.

Jantzer98SS

iTrader: (54)

Mine eats a little oil too, oh well. Everybody seems to. It still runs good, sounds good, and looks good.

Funny thing about my car is ever since the first head/cam swap, the oil pressure at idle is significantly lower and I have no idea why. 20psi is ok for idle and as long as it stays close to 8-10psi per 1000rpm I'll be comfortable.

The Emperor Of Darkness

so with heads/cam 20 psi is ok??!?!?! it seems kinda weird.

StrongWS6

Thats weird, my oil pump is a champ. At idle and normal driving my rpms are in between 40 and the hash mark. It actually increased a little after the cam swap. At WOT it goes all the way.

Stock mine was right past 40 I believe, so anything less you would think would be bad although the manual says as long as its not in that red area its okay?

bdawg/98mechamta#9

i think if oil pressure is low at idle , it COULD be the pick up tube O ring , thats what i think is making mine low at idle , i will find out soon , when the heads are off ( again )and the new cam ( different ) goes in , again

sawedoff

iTrader: (3)

It's real simple. If you're running a high volume pump, which you don't need, your running the pan dry. All of your oil is in the top of your engine. You're losing a shitload of power due to windage, when the oil comes back through. In my 99' Z28 1LE, I do the same thing I do in my circle track motors. First off at operating temp, at idle, my pressure is slightly under 40psi, at WOT it's at 60psi. I run a racing oil called Neo-Synthetic in 0w-5 weight. The old adage of an engine needing 10psi per 1000rpms is thrity years out of date. These engine only need about 50-60psi of oil pressure to do the job. The bearing clearances are tight, so you don't need to run a high viscocity oil, which raises pressure and creates heat. That's what kills an oil pump. You probably need an oil pan that holds more oil. In my circle track engines I run a pan that holds up to anywhere from 8 to 9 quarts, but I don't use that many quarts, only about 6.5. That keeps the oil in the pan from hitting your crank and acting like a brake, and creating windage probs. You might also try using a standard blueprinted oil pump that sees no more than 60psi max.

So, that's exactly what sounds like is going on in your case. I have friends that drag race, that tell me by the end of the quarter mile, they have no oil pressure at all. It's all in the top of the motor, which is fine for that type of racing, but not in other types. Also in a hard launch it's not uncommon for the oil in the pan to move completely away from the oil pickup, due to the force of the launch. You need a good oil pan, not a cheapy.

verbs

nope, just a stocker, not ported