How much oil pressure does your stock short block have?
07-29-2007, 08:19 PM
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How much oil pressure does your stock short block have? Just as stated. How much oil pressure does your stock short block have? I have been spraying the car at the track pretty hard and often. I would say I have about 100 passes with a 150 shot and a few with a total of 500rwhp. The car has been shifted as high as 6800 but usually at 6500. I'm now worried because I only have 20-28 psi @ 3000 and 6000 rpm.
07-29-2007, 08:24 PM
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Is this after an oil change? A lot of times if you start getting fuel in the oil, it can lean out the oil, and cause it to drop pressure. Is there any noticeable knock noises?
07-29-2007, 09:09 PM
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Originally Posted by jakesz28
Just as stated. How much oil pressure does your stock short block have? I have been spraying the car at the track pretty hard and often. I would say I have about 100 passes with a 150 shot and a few with a total of 500rwhp. The car has been shifted as high as 6800 but usually at 6500. I'm now worried because I only have 20-28 psi @ 3000 and 6000 rpm.
07-29-2007, 10:37 PM
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on a hot engine mine idles at around 20-22 psi cruising down the highway at about 1500 rpm i read about 37-40 psi at anything rpm above that it hovers right around 45 psi
on cold starts it runs about 45-50 psi thats with mobile 1 0W40
im sure you know this already but gm specifies atleast
6 psi at 1000 rpm
18 psi at 2000 rpm
26 psi at 4000 rpm
on cold starts it runs about 45-50 psi thats with mobile 1 0W40
im sure you know this already but gm specifies atleast
6 psi at 1000 rpm
18 psi at 2000 rpm
26 psi at 4000 rpm
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07-31-2007, 08:39 AM
#10
Mine was at about 20 hot idle about 50 cold start and maybe 55 when high RPM and 30 on highway. Installed a Melling 10% HV pump with the GM 'white' spring and now have 75 on startup and high RPM and 40 hot cruise lowest idle I've seen is about 30-35. This is on a stock 151k factory replacement 4 bolt block. Didn't think the new pump and spring would make that much difference.
07-31-2007, 12:54 PM
#11
You got a good Melling one in that new Engine there Corey..
I would definately look into a new Pump there Jake..they way these Engines work, the Pressure Sending Unit is fed from the Pump, so you are getting the direct pressure off of it. Think about how much you are loosing through the Engine.
The way the LSX's work is total opposite, the Pressure Sending Unit it the last thing in circulation, so when you hammer it, it drops. I idle at about 55-60 hot, and I put it down and it drops to 25..first time I saw that I was like WTF..
Then I started looking into it and did some checks, and it's fine. Still freaky **** when you are not used to it..
I would definately look into a new Pump there Jake..they way these Engines work, the Pressure Sending Unit is fed from the Pump, so you are getting the direct pressure off of it. Think about how much you are loosing through the Engine.
The way the LSX's work is total opposite, the Pressure Sending Unit it the last thing in circulation, so when you hammer it, it drops. I idle at about 55-60 hot, and I put it down and it drops to 25..first time I saw that I was like WTF..
Then I started looking into it and did some checks, and it's fine. Still freaky **** when you are not used to it..
07-31-2007, 01:23 PM
#12
what you need to do is a fresh oil change and buy a new sending unit...people dont understand theres only a piece of plastic like i guess a diaghram that stretches and wont read anymore...my friend car used to rear 10psi at idle and 20-full throttle, new sending unit he has 25 at idle and about 55 wot
07-31-2007, 02:22 PM
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yeah the oil sending unit is what it prob is mine went out in my old car 91 z28 and it would read like 5-0 psi at warm idle and 20-25 at wot i changed the unit and it had the best oil presure of any of my 4 camaros lol now the sending unit went out in my new car 93 z28 and its doing the same thing thing its a easy job and its only like a 35$ part... its realy comman for thouse to go out even more with mods.....
08-02-2007, 08:33 PM
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Well I don't think it is the sending unit. This car has been getting driven daily, up till the rearend broke. I have been driven it for a couple weeks after I put the nine inch in. I will change the oil and filter and see what that does.
The last time I raced it I left the line spraying 200rwhp. Then the spiders broke the motor went to 6800 on the rev limiter. One stage of nitrous shut off on the window switch and the second stage kept spraying. Had good oil pressure that day and now it is low. If the oil change don't help I may try changing the pump. In three weeks there is a two day event and I was going to run two classes and don't want to miss out.
How hard is it to get the oil pan off without pulling the motor?
The last time I raced it I left the line spraying 200rwhp. Then the spiders broke the motor went to 6800 on the rev limiter. One stage of nitrous shut off on the window switch and the second stage kept spraying. Had good oil pressure that day and now it is low. If the oil change don't help I may try changing the pump. In three weeks there is a two day event and I was going to run two classes and don't want to miss out.
How hard is it to get the oil pan off without pulling the motor?
08-04-2007, 12:13 PM
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Well I changed the oil and it is not good. All kinds of metal flakes. I need to open it up and see if I can see anything. It sounds good no strange noises or anything. But it is hurt bad.
I want to take it to a couple bigger races this year and I can't afford to build the motor I want so I think I will be looking for another motor to get to the end of the year. What really sucks is my truck needs a motor at the same time.
I want to take it to a couple bigger races this year and I can't afford to build the motor I want so I think I will be looking for another motor to get to the end of the year. What really sucks is my truck needs a motor at the same time.
08-04-2007, 12:51 PM
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Pan off in the car ain't fun! We tried it on a buddy's car and we had to take the transmission loose and put the engine as high as we could in the car with the intake off. Was able to weasel the pan off the back, getting around the pickup is the hardest part. To reinstall we slid it in from the front.
08-04-2007, 12:54 PM
#20
if theres a bunch of metal take the motor out now and inspect/replace all the bearings if nothing it torn up too bad, if not you may only be 1 mile from spining a rod or tearing up a main...course you might have 200 miles left in it...definately remove and inspect thouroughly, you can get all your bearings a rings and gaskets for less than 300 bucks...id refresh it and put it back together...then you can beat that thing for 2-3-4 years