Mobil1 0w40: LS7 Corvette Z06

[Dirty_Howie]

Originally Posted By: CATERHAM
There is nothing wrong with 60psi, the thing is most of the time the OP is much higher than that, meaning the oil is much heavier than necessary most of the time.
In a typical track session of say 25 minutes, for how long of the session has the oil temperature peaked at 255-260F with the corresponding drop in OP to 60 psi?

IIRC the oil pump by-pass point on the LS7 is set at 75-80 psi.
With M1 0W-40 what oil temperature to you need to avoid the oil pump going into by-pass mode at 6,500 rpm?



Well it was 90* out here in the So Cal desert so it the oil quickly got up to 240 and I would say at least 15 minutes. My coolant got up to 235 which I know retards timing and power (getting a real radiator in the next month or so).

I find the oil pressure is extremely consistant now that I switched from 5w30. Freeway cruising when cold or normal operating temps is 60. Pressure will spike when cold to 80 with any decent throttle input. Idle at normal operating temps is 35-40. And every time I looked today at the track it was 60. This track has no long straights so I could spend much time checking !!!

Any other info you would like, please ask. I hope you agree that this and my UAO confirms that this oil is good for my use.

DH

 

[Leo]

Seems the M1 0w40 is a good match for your engine. I wouldn't change a thing!

 

[CATERHAM]

Originally Posted By: Dirty_Howie
Originally Posted By: CATERHAM


Freeway cruising when cold or normal operating temps is 60. Pressure will spike when cold to 80 with any decent throttle input. Idle at normal operating temps is 35-40. And every time I looked today at the track it was 60. This track has no long straights so I could spend much time checking !!!
Any other info you would like, please ask. I hope you agree that this and my UAO confirms that this oil is good for my use.
DH

We're you at Willow Springs?
I'm getting antsy for the track season to start up here!

The reason the OP will spike on the street to the 80 psi by-pass point is because M1 0W-40 is too heavy for street use with the cooler oil temp's.
The advise I give to my track buddies that like to run heavier than spec' oil is to use your OP gauge as a variable red line.
That is don't rev the engine higher than the oil pump by-pass point.
DH, what you're finding is that you're unable to use maximum rev's on the street very often if at all without going into by-pass mode. And on the track, it can be quite frustrating waiting for 10-15 minutes before you can use maximum rev's with going into by-pass.

On the LS7 engine you can run the OP as low as 45 psi without a problem, but 50 psi is a nice conservative lower limit.
Because of your track use, I can see substituting a couple of qts of M1 0W-40 for the straight 5W-30 but I wouldn't be using more than that.
Another option is picking up a couple of qts of M1 R 0W-50 (HTHSV 4.1cP, 189 VI, 1,600 ppm moly and 2,500 ppm P).
Just adding one qt of this to a regular fill of M1 5W-30 will give you all the additional protection you'd want on track without unduly thickening the oil when operating at lower oil temp's.

Cheers

As

 

[Dirty_Howie]

Originally Posted By: CATERHAM
Originally Posted By: Dirty_Howie
Originally Posted By: CATERHAM


Freeway cruising when cold or normal operating temps is 60. Pressure will spike when cold to 80 with any decent throttle input. Idle at normal operating temps is 35-40. And every time I looked today at the track it was 60. This track has no long straights so I could spend much time checking !!!
Any other info you would like, please ask. I hope you agree that this and my UAO confirms that this oil is good for my use.
DH

We're you at Willow Springs?
I'm getting antsy for the track season to start up here!

The reason the OP will spike on the street to the 80 psi by-pass point is because M1 0W-40 is too heavy for street use with the cooler oil temp's.
The advise I give to my track buddies that like to run heavier than spec' oil is to use your OP gauge as a variable red line.
That is don't rev the engine higher than the oil pump by-pass point.
DH, what you're finding is that you're unable to use maximum rev's on the street very often if at all without going into by-pass mode. And on the track, it can be quite frustrating waiting for 10-15 minutes before you can use maximum rev's with going into by-pass.

On the LS7 engine you can run the OP as low as 45 psi without a problem, but 50 psi is a nice conservative lower limit.
Because of your track use, I can see substituting a couple of qts of M1 0W-40 for the straight 5W-30 but I wouldn't be using more than that.
Another option is picking up a couple of qts of M1 R 0W-50 (HTHSV 4.1cP, 189 VI, 1,600 ppm moly and 2,500 ppm P).
Just adding one qt of this to a regular fill of M1 5W-30 will give you all the additional protection you'd want on track without unduly thickening the oil when operating at lower oil temp's.

Cheers

As


Thanks for the insight !!

DH

 

[MobilinHyundia]

I was thinking of using a scangauge 2 ( ind RPM) and a oil pressure setup.
To monitor the readings, I will use a small camera to record the readings.
That way I dont have to stare at the gauges while driving.