Low oil pressure or just paranoia?

[E30Delara]

Could use some insight on my "problem", I'd appreciate it. Story Time, haha. Sorry if it ends up being long winded, but I'd like to give as much info as possible. I have looked and read up on so many "Low Oil Pressure" related problems, on ZL1's and CTS-V's.

So a couple days ago I was driving my car and came upon a nice empty stretch of road, nothing but a red stop lighting holding me back. I eased onto the throttle in first and shifted into second, got up to 4k rpm's and let her rip. Now I had a new pair of shoes on, and I had never gone WOT with them, well, my foot kinda slipped off the clutch and I didn't hit third. No grinding or anything of the sort, just didn't get it in. Unfortunately, I hit the limiter, first time since I've owned the car. Fast forward, I'm driving down the freeway and look at my Oil Pressure Gauge, I'm cruising around 2,100 rpm's and it's reading 3.2-3.1 Bar. I always remember it being at 3.8 at cruise, unfortunately, I don't remember my reading at anything above that, other than it always went past 4+ Bar when I was closer to redline(5k+).

So now, at idle I get around 2.2-2.5 Bar warmed up(90+ temps), and 3.4 Bar when at 3,500 rp'ms+. It doesn't get any higher as the rpm's progress, I've actually seen it drop .1-.2 Bar when getting above 5k. I drove it around today after changing the oil and it stays pretty consistent, but I can't help but wonder that it should be higher. Did a few WOT pulls and the psi values stayed the same, as mentioned earlier. Also, when driving and giving it gas and then letting off, the oil pressure will go up .1-.2 Bar. When changing the oil, I didn't notice any kind flakes, other than some gold/bronze glitter from the oil filter, but I believe that's from my CHE Trunnion kit.

So could have hitting the Rev limiter(Limiter set at 6800, per my tuner) caused this new "problem" or am I just being paranoid?
What do your guys Oil Pressure read as your rpm's increase?

Mod List
GP Tuning Stage 2 Cam(with Supporting Mods)
Melling 10355
Kong Ported SC
10" Pulley
ID1050x
Headers
Roto-Fab
MM Catch Can

Thanks for any help you guys can give.

[Crash76]

Convert bar to psi for me lol

[Crash76]

Oil drop due to over reving would be damaged bearings. Unless the pump has an issue

you are at about the recommended max 23000rpm for the supercharger with at 10” lower and stock snout pulley with 6800rpm engine rpm

If you cannot be sure of the oil pressure before the rev limiter incident, we cannot know that is the cause...

I idle around 30psi warm

I believe there is a bypass valve in the pump so the psi wont go through the roof


We should gtg sometime... i see you are in my neck of the woods

[DrkPhx]

Blower rpm aside, I'm still surprised to see so many spin these engines that high on stock heads with these heavy valves. I included some bar to psi conversions below.

If the oil pressure is dropping at WOT check the oil level first. The oil pump is crank driven, so the pressure will change depending on the engine rpm.

This is not good and not related to the trunion kit:

other than some gold/bronze glitter from the oil filter

Sounds like cam bearing material which is actually copper. Your current readings are right in line with a normal LSA on a stock pump, but oil pressure with a Melling pump is usually higher, so as mentioned above it's hard to say without comparing those to the previous reading.

Bar to psi approximate conversion:

Bar PSI
1 15
1.5 22
2 29
2.5 36
3 44
3.5 51
4 58
4.5 65
5 73
5.5 80
6 87

[DrkPhx]

Also check the catch can to see if there are metal flakes at the bottom.

[RobZL1]

I don't see how you would ever get over 3.4-3.8 bar at WOT when hot unless you remove and plug the oil sump relief valve, which limits pressure to right around 3.8 bar. Even if you were to shim the 10355, it would still be limited at the top of the pressure range due to the relief. I guess you could run a very thick oil to get there, to the point where the relief can't keep up with the flow and thickness of the oil, I mean.

I just checked my data log from last week- at WOT, pressure is 3.2-3.4 at 2000 rpm and then stays between there and 3.4-3.6 bar max all the way to my 6700rpm fuel cut. I only see higher (and then only up to 3.9-4.0 bar) at initial start up in the morning and during the first 15 minutes or so of my drive when it's cooler outside.

When hot and cruising, I see 3.2-3.3 bar. When hot at idle, I see 2.5 bar.

My mods are about the same: 10", GP 2.5 cam, ported melling 10355, CHE trunions, etc.

Is this your first oil change after the cam/ kit? If so, that might explain the brass from the CHE break-in. Also, what oil are you running? I run Redline 5w30- which is thicker than the off-the-shelf synthetic stuff of the same weight.

[E30Delara]

Originally Posted by Crash76

Oil drop due to over reving would be damaged bearings. Unless the pump has an issue

you are at about the recommended max 23000rpm for the supercharger with at 10” lower and stock snout pulley with 6800rpm engine rpm

If you cannot be sure of the oil pressure before the rev limiter incident, we cannot know that is the cause...

I idle around 30psi warm

I believe there is a bypass valve in the pump so the psi wont go through the roof


We should gtg sometime... i see you are in my neck of the woods

Those are my worst fears right now, I was hoping you guys would tell me that something went wrong with the Oil Pump. Unfortunately, I don't really remember my previous oil pressure, I do remember that it did idle around 2.8 Bar(41.16psi). By going off of your idle, I'm about the same 2.2-2.4 Bar(32.34-35.28psi). Also, my Pulleys are;

ZPE 2.90 Upper and DSX 9.84 Lower

Yeah, that sounds good, I'm always down to meet new people/car enthusiast. I'm actually in Tracy, but frequent the Bay Area.

Originally Posted by DrkPhx

Blower rpm aside, I'm still surprised to see so many spin these engines that high on stock heads with these heavy valves. I included some bar to psi conversions below.

If the oil pressure is dropping at WOT check the oil level first. The oil pump is crank driven, so the pressure will change depending on the engine rpm.

This is not good and not related to the trunion kit:


Sounds like cam bearing material which is actually copper. Your current readings are right in line with a normal LSA on a stock pump, but oil pressure with a Melling pump is usually higher, so as mentioned above it's hard to say without comparing those to the previous reading.

Bar to psi approximate conversion:

Bar PSI
1 15
1.5 22
2 29
2.5 36
3 44
3.5 51
4 58
4.5 65
5 73
5.5 80
6 87

According to my tuner, which does many LSA vehicles, with my supporting mods, he's seen people revving to 7,200rpm. I didn't feel comfortable with that, so he put my limiter at 6800, I shift around 6,500rpm.

I did an oil change yesterday and checked my level, it's at the top dot/indicator. The oil pressure drops .1-.2 bar (1.47-2.94psi) once I'm about to shift, sometimes it doesn't move at all, very intermittent.

As for the glitter I mentioned earlier, I'm going to try and post a pic. I was reading on another forum and it looks to be the same as to what I have, and they said it was from their Trunnion kit.

Originally Posted by DrkPhx

Also check the catch can to see if there are metal flakes at the bottom.

I will check that today.

Thanks for your guy's insight, it's greatly appreciated.

[E30Delara]

Originally Posted by RobZL1

I don't see how you would ever get over 3.4-3.8 bar at WOT when hot unless you remove and plug the oil sump relief valve, which limits pressure to right around 3.8 bar. Even if you were to shim the 10355, it would still be limited at the top of the pressure range due to the relief. I guess you could run a very thick oil to get there, to the point where the relief can't keep up with the flow and thickness of the oil, I mean.

I just checked my data log from last week- at WOT, pressure is 3.2-3.4 at 2000 rpm and then stays between there and 3.4-3.6 bar max all the way to my 6700rpm fuel cut. I only see higher (and then only up to 3.9-4.0 bar) at initial start up in the morning and during the first 15 minutes or so of my drive when it's cooler outside.

When hot and cruising, I see 3.2-3.3 bar. When hot at idle, I see 2.5 bar.

My mods are about the same: 10", GP 2.5 cam, ported melling 10355, CHE trunions, etc.

Is this your first oil change after the cam/ kit? If so, that might explain the brass from the CHE break-in. Also, what oil are you running? I run Redline 5w30- which is thicker than the off-the-shelf synthetic stuff of the same weight.

I tried to check my data logs for a few runs that I had previously, unfortunately, it didn't seem to have Oil Pressure on there(HPTuners). I'll try to compare my oil pressure with yours below.

95*-100* Ambient Temps
2000 rpm= 3.0-3.2
6500 rpm= 3.3-3.4(Seen it go from 3.4 down to 3.3 so far)
Cold Start= 3.9-4.0(750 rpm)

Does your oil pressure go down slightly when you're driving at cruise speeds and you let off the throttle a bit? Example:

2100-2200 rpm= 3.1-3.2 Bar
Let off down to 1900-200 rpm 3.0-3.1 respectively.
Then back up when getting back on the gas.

Yes, this is my first oil change after the cam swap. I was and am running Pennzoil Ultra Platinum before and now after the oil change. I always wondered if I should change the oil weight due to my area's temps and the cam swap, maybe to a 5w-40? As for the brand, there are so many to choose from, I just used what was readily available. I read Redline, Amsoil, Royal Purple, Joe Gibbs. It's so hard to pick, I might try Redline or Amsoil next.

I appreciate your input!

[lemontwist]

looks like glitter

[RobZL1]

Originally Posted by E30Delara

I tried to check my data logs for a few runs that I had previously, unfortunately, it didn't seem to have Oil Pressure on there(HPTuners). I'll try to compare my oil pressure with yours below.

95*-100* Ambient Temps
2000 rpm= 3.0-3.2
6500 rpm= 3.3-3.4(Seen it go from 3.4 down to 3.3 so far)
Cold Start= 3.9-4.0(750 rpm)

Does your oil pressure go down slightly when you're driving at cruise speeds and you let off the throttle a bit? Example:

2100-2200 rpm= 3.1-3.2 Bar
Let off down to 1900-200 rpm 3.0-3.1 respectively.
Then back up when getting back on the gas.

Yes, this is my first oil change after the cam swap. I was and am running Pennzoil Ultra Platinum before and now after the oil change. I always wondered if I should change the oil weight due to my area's temps and the cam swap, maybe to a 5w-40? As for the brand, there are so many to choose from, I just used what was readily available. I read Redline, Amsoil, Royal Purple, Joe Gibbs. It's so hard to pick, I might try Redline or Amsoil next.

I appreciate your input!

My pressure will either stay constant or drop a tenth when RPM drops a few hundred during an off-the-gas cruise transition.

I'd be willing to bet the flecks you see are from the CHE break-in since this is the first oil change- that said, hopefully your builder used some sort of assembly lube on all of the fresh components.

Regarding oil brand, a good full synthetic is the way to go with the increased spring pressures pushing on the lifters and higher RPM that come with a cam. Personally, I'd only run Redline, Joe Gibbs LS Driven, or maybe Amsoil. I'd avoid anything off the shelf, honestly (Mobil1, Pennzoil, etc.). I know that's personal opinion, and oil is highly controversial, but most people running higher HP builds swear by one of the three I mentioned. Speaking of GP cams, I believe Matt recommends and uses Redline and Driven in his builds. I'd think a 5w30 would be fine, and I know some will run a 5w40, though. Just remember that the better oils have a higher viscosity than the off-the-shelf stuff at the same advertised weight- e.g., I believe I read that the Redline 5w30 has the same or higher viscosity as Mobil1 5w40.

[E30Delara]

Originally Posted by RobZL1

My pressure will either stay constant or drop a tenth when RPM drops a few hundred during an off-the-gas cruise transition.

I'd be willing to bet the flecks you see are from the CHE break-in since this is the first oil change- that said, hopefully your builder used some sort of assembly lube on all of the fresh components.

Regarding oil brand, a good full synthetic is the way to go with the increased spring pressures pushing on the lifters and higher RPM that come with a cam. Personally, I'd only run Redline, Joe Gibbs LS Driven, or maybe Amsoil. I'd avoid anything off the shelf, honestly (Mobil1, Pennzoil, etc.). I know that's personal opinion, and oil is highly controversial, but most people running higher HP builds swear by one of the three I mentioned. Speaking of GP cams, I believe Matt recommends and uses Redline and Driven in his builds. I'd think a 5w30 would be fine, and I know some will run a 5w40, though. Just remember that the better oils have a higher viscosity than the off-the-shelf stuff at the same advertised weight- e.g., I believe I read that the Redline 5w30 has the same or higher viscosity as Mobil1 5w40.

My friend and I installed almost everything back in the beginning of May. There was assembly lube on everything that needed it. As for the glitter/flecks, I believe it to be from the CHE kit as well. I'm going to order Redline and change out my oil this week.

I'm starting to feel a little more at ease after all your guy's input, maybe I was just being paranoid, since I thought I might have hurt something when hitting the limiter. Just for anyone else in my situation, I'm going to update the thread later, after the oil change.

[silversleeper]

Originally Posted by DrkPhx

Also check the catch can to see if there are metal flakes at the bottom.

[Wattabanana]

It may have been mentioned already but I vote for Redline as well and strongly suggest a WIX filter, I use the 57045XP. The belly pan needs the slightest trim to clear.

A proper filter cutting would show more info. I concur, the glitter is likely not bearings but the filter doesn't lie.

Also FWIW my bone stock 14' has never made 4 bar and I've got 20W50 Redline in it.

Good luck

[E30Delara]

Originally Posted by Wattabanana

It may have been mentioned already but I vote for Redline as well and strongly suggest a WIX filter, I use the 57045XP. The belly pan needs the slightest trim to clear.

A proper filter cutting would show more info. I concur, the glitter is likely not bearings but the filter doesn't lie.

Also FWIW my bone stock 14' has never made 4 bar and I've got 20W50 Redline in it.

Good luck

Thanks, I need it, haha.

Already got everything on order, Redline 5w-30 and Wix 57060XP. Ordered it before I saw your post, but that filter you mentioned seems quite a bit larger than the one I found to be for a ZL1. Unfortunately, I already threw away the old filter, but will be looking at the next one on Thursday. Everything is arriving on Wednesday. I don't really drive my car on the weekdays, but already did quite a bit of WOT pulls this weekend, so if anything, the filter will show if anything is out of the ordinary.