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Bought my 05 V last year from an older gentleman that seemed to have treat her with much love. I picked her up with about 50k miles on the clock. It came from the previous owner already slightly modified and running perfect. For a quick list to maybe help with my issue, it has a 92mm FAST intake manifold, upgraded 42lb(?)Injectors, upgraded fuel rail, kooks long tube headers, corsa exhaust, volant cold air intake, I’m not sure which exact cam(he said stage 3 race cam), high flow fuel pump, g-force 1320 axles. The car has had a tune from rpm motor sports by the previous owner. I recently installed an ls7 clutch since the stock clutch seemed to not like going in reverse like it was too tall for the slave cylinder to want to clear. I also threw some creative steel shift bushings and motor mounts in as well.

Here’s my issue as far as cam, oil pressure, and perhaps min bearing failure....
Over the past week or so I’ve notice at cold start up and idle I’m around 25-30 psi. After warmup and idling hot at around 190 degrees with an oil temp of about 180-200 the oil pressure drops as low as 10lbs!!! That’s too low!!! When I rev up to about 2k rpm the psi shoots back up to 25-30 psi and at about 3k rpm it’s at 35-40 psi. Driving down the Interstate doing 70-75mph in 6th gear at about 14-16k rpm I get about 15-18psi consintently now. These a very low numbers and I’m worried about limping her along too much longer with rebuilding the entire motor. Obviously this needs to be taken care of ASAP. Does this sound like a main bearing issue that somehow the bearing got etched/scored during the cam install and now it’s getting worse? Or perhaps is this just a failing oil pump? Advice on what to do or what exactly this might be please! I’ve searched and found so many threads about all sorts of oil pressure issues I’m syarting to go cross eyed and just thought I would post instead. Thanks in advance for any help guys.
 

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I've always noticed the higher you rev it, the oil pressure follows...
 

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I've always noticed the higher you rev it, the oil pressure follows...
Exactly as it should. The oil pump is driven by the engine/crankshaft directly, so the oil pump rpm changes directly with engine rpm, not with load or throttle. So as the rpms rise, so will oil pressure (to a limit - either the limit of the pump or the limit of the relief valve).

Pretty sure Duck or Steck or some of the other more knowledgeable guys have posted some kind of relationship between rpm and pressure that represents kinda where things should be. At the upper range, I feel like it should be around 75-85psi IIRC. Anyway = point is I seem to recall noting oil pressure at various rpms is a good way to validate that the pump and flow is working as it should.
 

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Discussion Starter #6
The more and more I read I’m worried I might be the victim to a spun main bearing. I changed the oil and filter last night and noticed very very fine metal sticking to the magnetic oil drain plug. I haven’t cut the filter open yet to see if I have any larger flakes or chunks.

I’m not going to start it any more until I can confirm what’s going on. It sounds like to me the oil pump is working with the increase in rpm comes the increase in pressure. The pressure is just very low. Which means it’s perhaps more likely a Bearing clearance issue? What other signs, ways to tell a main bearing is the culprit? It does seem like my exhaust was a bit louder than normal at load and a very slight vibration... almost like a bad tire balance the last time I did drive it.
 

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Exactly as it should. The oil pump is driven by the engine/crankshaft directly, so the oil pump rpm changes directly with engine rpm, not with load or throttle. So as the rpms rise, so will oil pressure (to a limit - either the limit of the pump or the limit of the relief valve).

Pretty sure Duck or Steck or some of the other more knowledgeable guys have posted some kind of relationship between rpm and pressure that represents kinda where things should be. At the upper range, I feel like it should be around 75-85psi IIRC. Anyway = point is I seem to recall noting oil pressure at various rpms is a good way to validate that the pump and flow is working as it should.
Haha Yes, I understand Tri, I was just playing around. I didn't really want him to rev the shit out of his 0 oil pressure motor. Haha
 

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That oil pressure is too low. If it were mine I would start tearing into it investigating what may be causing the issue. I would also have a new oil pump to install when I got there. Start with the oil and oil filter, looking for metal shavings. If you see any shavings, it's time to start over.
 

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Have you taken your oil pressure measurement with a mechanical gauge to verify the accuracy of the dash gauge? V1s are notorious for have oil pressure sensor failures. I would do this first. Also, cutting open the oil filter to look for bearing material is not a bad idea.

I had the same issue on my 2004 V. Ended up being the oil pressure sensor. It is easy to replace as it is located at the rear of the engine on top on the driver's side.

Hope you are lucky.
 
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