Oil weight for track/street car question

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Feb 9, 2021
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Alright guys so my engine is a VQ35HR which are notoriously hard on oil. I track it about 6 times a year and its getting to where it mostly sees track use but I do like to putter around the city in it as well.

OEM recomendation is 5w-30. I have been running 0W-40 Mobil One. My oil temp on track used to be around 290. I put in an oil cooler. It went down to 275-280. So over the winter I installed a horizonally mounted dual pass bar and plate oil cooler in my splitter. It is crazy effective. I'm down to 230 and it does not go higher than that. I am redlining it the entire time on track. Half an hour straight, 5-7 sessions per track day. I block off the cooler with a composite plate so it doesn't overcool on the street. Street temps are around 185-210 depending on temperature.

With all that said, is there any reason for me to be running the higher weight oil if my temps are that low on track now. Am I just costing myself HP loss and messing up my variable camshaft timing by running a slightly different weight?
 
I highly doubt you are messing up the variable camshaft timing by running a grade thicker. If you want to run a xW-30 go with a Euro spec oil that has HTSH of 3.5 cP or better. If the oil temps only get to 230F during hard extended track use because the oil cooler is effective then xW-30 Euro spec would probably be fine. The xW-30 might even run a little cooler on the track with the cooler. If there is any doubt then stay with what you're doing.
 
Stick what you using! Oil cooler is the key.
Any oil with Porsche A40 approval is basically track rated as approval is consisting test that includes 5X1hrs Nordschleife simulated track time.
Edit: why don’t you install oil cooler thermostat?
 
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What is the oil sump volume? 4 quarts like the rest of the Nissan VQ's that I'm familiar with? I think that is the major reason the VQ has a reputation for being hard on oil.
Have you done any UOA's? I would be curious to see if the VQ is shearing the wide viscosity spread 0w40 into the 30 grade.
The M1 0w40 is right at the low end of the 40 grade, and it wouldn't take much to push it into 30 territory. Not that it would be a problem because the VQ is spec'd for 30.
Good job of getting an effective oil cooler on it.
 
What is the oil sump volume? 4 quarts like the rest of the Nissan VQ's that I'm familiar with? I think that is the major reason the VQ has a reputation for being hard on oil.
Have you done any UOA's? I would be curious to see if the VQ is shearing the wide viscosity spread 0w40 into the 30 grade.
The M1 0w40 is right at the low end of the 40 grade, and it wouldn't take much to push it into 30 territory. Not that it would be a problem because the VQ is spec'd for 30.
Good job of getting an effective oil cooler on it.
I am not into Nissan's, but I find this ridiculous. Though, Honda Pilot I have is like 4.5qt.
Still, in a vehicle like that such a low sump? My 3ltr BMW takes over 7qt.
 
Capture+_2022-06-12-21-00-23.jpg
 
I'm still wondering what car the op is driving? I see it's used in a variety of applications:
Infiniti G35 Sedan2007–2008
Nissan Skyline V36 350GT Sedan2007–2008
Nissan 350Z2007–2008
Nissan Fuga 350 GT2006–2008
Infiniti EX352008–2012
Infiniti FX352009–2012
Infiniti M352009–2010
Infiniti M35h2011–2013
Infiniti M35h2011–2013
Infiniti M35h2011–2013
Nissan Fuga Hybrid2010–
Nissan Cima2012–
Mitsubishi Dignity2012–
Infiniti Q50 Hybrid2014–
Infiniti Q70 Hybrid2014–
 
I highly doubt you are messing up the variable camshaft timing by running a grade thicker. If you want to run a xW-30 go with a Euro spec oil that has HTSH of 3.5 cP or better. If the oil temps only get to 230F during hard extended track use because the oil cooler is effective then xW-30 Euro spec would probably be fine. The xW-30 might even run a little cooler on the track with the cooler. If there is any doubt then stay with what you're doing.
And a 40-grade with essentially the same HT/HS as that 5W-30 has a truly negligible difference in viscosity at operating temperature. Running a "slightly different weight" is inconsequential here.
 
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I'm assuming you change it immediately following track days? I know I sure would but that M1 Euro 0-40 should be just fine for your uses. My GT500 calls for 5-50 but I always run either RP HPS 5-30 or M1 Euro 0-40. It has the euro 0-40 in it for this summer, I don't track her though.
 
I'm assuming you change it immediately following track days? I know I sure would but that M1 Euro 0-40 should be just fine for your uses. My GT500 calls for 5-50 but I always run either RP HPS 5-30 or M1 Euro 0-40. It has the euro 0-40 in it for this summer, I don't track her though.
Why changing immediately? I run 5k interval on 3-4 track days.
 
I don't think 15w50 is a bad choice at all. I also don't think M1 0w40 is either. OP has already done his due diligence by installing an oil cooler and monitoring oil temps. Only thing I would suggest adding is a thermostat to the oil cooler circuit. I've used Mocal in the past with good results.
 
I don't think you'll see any race teams doing that
Hmmm, ok, I am not sure what that has to do with open lapping track fun?
Here is UOA of Castrol Edge 0W40 with sessions as 1 1/2hrs long, around 100 degrees ambient temperature and 5,000ft altitude, and two child seats in the rear:
130913CE-48E1-4900-939D-D1DB89924CA0.jpeg

The right UOA is no track time. So, tell me why should I change oil after one track day?
 
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Awesome. Honestly, I didn't expect that non-existent difference.
Apparently that N52 (?) loves extended periods at high revs.
That doesn't necessarily apply to any kind of ICE though.
.
 
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