waddisme

I usually keep my DIC on oil temps, but because my accusump was out (again), I kept it on the oil pressure reading. So Monday at VIR, I watched it on the backstretch during a WOT run in 4th from 90mph to 149mph. At 249*, pressure started at 29lbs and went to 30lbs. That was it. I thought it was supposed to go up like 10lbs per 1000rpm. I have an oil cooler with -10an lines going to the big Setrab cooler with the LPE block adapter. Do I have a restriction somewhere or is that just normal? Motor is a forged aluminum LS2 with ported and shimmed LS6 oil pump.

2MCHPWR

you didn't mention the oil you use.
I was running Mobil 1 5w-30 and after a few HARD laps, pressure would not go over 40 psi. I think max was like 37 actually.
I did some research and switch to Amsoil Dominator 10w-30 and now it's making over 50 psi throughout the session I've read the mobil gets too thin when hot.

RX-Ben

Something seems wrong. I had that issue, I think something went wrong on my takeoff block (running an OEM C6 takeoff to a DeWitts at the time). I switch to a Setrab/ECS takeoff block and all was better.
You should have at least ~50psi in the 5500+ range, from what I have read. There is a table somewhere of min pressure vs RPM (based on a GM manual for I think an Fbody), but I don't think that goes north of 4000 rpm. You might be able to find a pic of the relevant page on the internets.

waddisme

Using Mobil1 10-40. Mine is the Lingenfelter adapter, so I don't think I am the first to use it. I have been using it for the past 4 yrs, but honestly, I have never really pd attention to oil pressure. During cool down session, I would look at it, but it was always around 30ish so I was never concerned. Will do some more research. Thanks.

pkincy

My LS2 402 would drop to about 30 psi at speed when oil temps got up to 280 deg F or so. Because of that I ran 15-50 Mobil 1 in the car that past few years during track events.

That was with both a TSP ported LS6 pump and than later a Melling Hi Pressure Pump.

I sold the car or I would have switched to the 10-60 Castrol that BMW uses in their E46 M3s. Mostly since I sold the M3 and have several cases of the Castrol lying around.

TKOGTO

Same low psi's here regardless which oil. Started with Amsoil 10w-30. I feed a qt of M1 15-50 before a track day and bleed a qt after. So far, little change, high 30's low 40's. Oil analysis showed higher levels of iron. However I have had to spend all my time/money this season trying to address 255 - 275* temps in the tranny. I have a DeWitts like RX Ben so I have to look into that.

Will be interested to see how this turns out for OP.

C6 LS3 BTW, no upgrades beyond intake and tune.

CHJ In Virginia

That pressure is low, there is some kind of restriction in your system or the pump is starting to give up. I run Mobil 1 5/30 and have the DRM separate external oil cooler system. All LS6 internals are stock. At VIR on the back straight - 140 MPH 6000 rpm and I am showing 50-55 PSI depending on temp of oil usually about 240 deg.

froggy47

That's low, you have a restriction, or failing pump, or oil wgt too low. I would get a Blackstone analisys.

pkincy

There is way too much variance motor to motor to talk about this on the internet.

The OP has a forged bottom end. We don't have a clue what clearances were used in his motor. When mine was built we went towards the loose side on each important oil bearing surface so I naturally had lower oil pressure than a stock motor. We also made certain that the oil galleys were open so oil wouldn't get caught in the top of the motor.

This comparison of oil pressures engine builder to OEM to another engine builder is ridiculous.

waddisme

Here is my last Blackstone from last summer before switching to Mobile1. As I only have 3 track days on the Mobil1, I haven't had one done this summer. Not sure what I would be looking for here. I don't ever recall seeing oil pressures in the 50s so I don't think this is something new, but just something I just noticed. But it is concerning.

froggy47

#9 has a point, can you talk to the builder? Or did you buy the car with the motor already done?

RX-Ben

Yes, builds are different, but I thought oil pressure mattered as regardless of the build/clearances, you still need to find a way to build enough oil pressure to enable the journal bearings to properly function.

waddisme

The bottom end came assembled from Texas Speed Performance. I will give them a call tomorrow.

froggy47

If they say it's good at least you'll have some peace of mind. Maybe it was always there once it got broken in.

Let us know.

pkincy

Same place I sourced my short block. However it was rebuilt twice in Phoenix due to spun bearings and scored crank. To many tight left turns at Firebird West with race tires and a good suspension. So the bearing clearances were different than what TSP used initially.

Good oil pressure just too many continuous tight left turns on that track at the top of 2nd gear.

naschmitz

Here's a lap of the VIR Full course for a lap during Friday at SVT SuperFest in May. I choose this lap because it was a day I know you were running there too.

LS2 motor, no mods. Mobil 1 0W40.

Turn 4 is the low RPM, low pressure left hand turn.
Turn 3 is the 4000-4500rpm 25 psi turn.
Bulk of the data is linear between 35psi and 50psi.

Ignore the kPa units label -- these are PSI.

waddisme

Awesome graph. Is that from OBDII data source?

naschmitz

Aim Solo DL connected to OBDII and plotted in Race Studio Analysis. You can cross reference it to the track map to identify where the conditions are occurring. It is pretty neat software.

waddisme

Just got off the phone with Texas Speed. According to them, the pressure should build as the RPMs increase. He said it sounds like there is a restriction. I am guessing I should start with the LPE block off adapter. I could put stock one on and not run oil cooler and see how it does. That would narrow it down to internals (oil pump) or externals (adapter or oil cooler). Is that the way to go?

RX-Ben

Yup. I would start even easier and just loop the lines that connect to your oil cooler, as the first step. An oil cooler acts, unintentionally, as an oil filter. Decent chance there is stuff in there and the cooler is the easiest thing to remove from the system.