Bob Bondurant School -- Corvette Oil Selection

[Matt_N]

BITOG'ers

I had the pleasure of completing a 3-day Grand Prix Racing school at the Bob Bondurant School of High Performance Driving in Arizona this week. My employer (Goodyear) is the tire sponsor for this school, so I had great access to all areas of the facility.

Most notably, I took some time to ask the mechanics what fluids they used in their fleet of cars for the school. They currently have a fleet of C6 Corvettes with the Z51 package, C6 Z06 Corvettes, a handful of ZR1's, as well as CTS, CTS-V, G8, Solstice, and others. Their fluid choices are as follows (note; school is also sponsored by Mobil 1):

Anything with an LS-based engine (Corvette's & CTS-V) gets Mobil 1 15w-50 motor oil. This makes sense with the Arizona climate. All other vehicles get Mobil 1 5w30. I was impressed with the 15w-50 selection; their C6 cars are 2008 model year and most have between 14,000-20,000 TRACK miles on them. They haven't had any engine related failures.

Also of note; brake fluid is Castrol SRF 600 in all vehicles (pads are Performance Friction Racing pads). Gearbox and differential fluids are those sold by GM.

I thought it was interesting to know what fluid was used by this school in their LS-motors, and wanted to share that info with all of you.

Matt

 

[buster]

Quote:
note; school is also sponsored by Mobil 1


Obviously a reason why they use M1. Money and it works.

 

[hate2work]

Originally Posted By: buster
Quote:
note; school is also sponsored by Mobil 1


Obviously a reason why they use M1. Money and it works.


Yep, and did you mention the money?

 

[rpn453]

Thanks for sharing. I asked a lot of questions while there, but didn't even think to ask about oil. Too much else going on. I'll have to let my Z06-owning buddy know. I recommended a thicker oil for hot track use but got no response to that particular advice, so I'm not sure if he agrees with going thicker than what the manufacturer recommends for street use.

You should have added the extra day while you were there. The Formula Mazda race cars are even more fun than the Vettes!

 

[XS650]

Originally Posted By: rpn453
Thanks for sharing. I asked a lot of questions while there, but didn't even think to ask about oil. Too much else going on. I'll have to let my Z06-owning buddy know. I recommended a thicker oil for hot track use but got no response to that particular advice, so I'm not sure if he agrees with going thicker than what the manufacturer recommends for street use.

You should have added the extra day while you were there. The Formula Mazda race cars are even more fun than the Vettes!


The C6 based Z06 doesn't need the thicker oil as much as the base model C6 and Z-51 C6
..
The Z06 has a big oil cooler and it's oil runs 25-40 degrees cooler then the others.

 

[AzFireGuy79]

Pretty interesting and a great driving school. Although there is absolutely no need to run a 50wt here in AZ. Does not hurt anything, but it also does not provide any superior protection. Plenty of 1000+hp LS cars racing on 30wt and surviving.

 

[buster]

Yeah the 15w50 could be making things worse actually.

 

[SuperFast]

Originally Posted By: buster
Yeah the 15w50 could be making things worse actually.


How.

?

I want to hear this.

50-wt oil has its poace in cars. Im proud of them for using it in certain cars. Seems they, a professional driving school sponsored by M1 (lost respect for them there, they are supposed to be abotut the spirit of driving not sponsoring kool aid) use a 50wt for good reason.

Probably becuase they thrash the living helll out of the cars, and it provides good protection. Much like tracked Porsches and BMWS! And Ferraris! and gues what ols THEY use

*ding* commence attacks on 50-wt oil. And being in Arizona, im sure it DOE make a lot of sense.

Dr Haas's cars would EXPLODE on their 20 and 30-wt. oil if given the Bob Bondurant treatment. I think he even says this, as he drives them like 2 miles then shuts them off. Must be nice.

So. Commence attack on good oil. Even M1 ?

 

[buster]

Well, for long endurance racing a higher grade is preferred to compensate for fuel dilution. My thinking was more heat, less hp and drag.

 

[SuperFast]

Originally Posted By: buster
Well, for long endurance racing a higher grade is preferred to compensate for fuel dilution. My thinking was more heat, less hp and drag.

And, those engines are trashed to begin with. High heat, high stress on engine = 50 wt. And Arizoa is HOT! ANd they driver it HARD!

On the next thing, i always did wonder why high performance cars liek Ferrari have 10W-60 (5W60> never heard of nor seen) oil in them, whereas maybe even a 40-wt would be ok. But they put it in there.

How much power wa slost? At 660HP, .. would it be more like 670 or so with thinner Oil?

Never understood that

if fuel delivery could be controllled, i wonder if they could use thin Oil

but its just a thought, Bob Bondurant Corvetttes get so trashed in think 5W-50 is the only thing holding some tigether.

Seriouslym, they drive the cars in a way that woul dbreak em. And eventually will...

How about Bob Bondurant's Exotics? They DO have them. ?

 

[A_Harman]

The 15w50 is probably just for extra insurance in the Arizona heat. And since Mobil 1 15w50 has higher zddp, that doesn't hurt either. Those engines are proven capable of running at full power for at least 300 hours on 5w30 oil when they are developed at General Motors. And the engines must be able to pass those tests and stay within original build tolerances. Most auto manufacturers have similar durability requirements.

How could 15w50 make things worse? Because of the higher viscosity, there would be a tendency for the stabilized oil temperature to be higher than if they were running a 5w30. There are a few factors from higher viscosity that could contribute to this:
1. More heat generation when the oil runs through the bearings.
2. Slower rate of oil drainage back to the sump, making oil starvation in the turns more of a possibility.
3. Lower rate of heat transfer in the oil cooler.

I don't know if these effects would cause an increase of 5F or 40F in the oil temperature, but they are all in the wrong direction using higher viscosity oil. As long as the oil temperature can be controlled to a maximum of ~230F in the main oil gallery, 5w30 would work OK, even in the desert.

 

[Matt_N]

Having sat behind the wheel of a C6/Z51 for a 30min open lapping session on the Firebird West Course, I can tell you that oil pressure remained nearly constant at 40psi the entire time I drove the car. Temps were 70F there last week. I can't say that I think 15w-50 was hurting the cars.

My thoughts on sponsorship -- when you go through as much oil / brakes / tires / etc as that school does, you need to have sponsors just to offset the operating costs. While we can debate whether (or not) each sponsor is the absolute best in their field, we can also safely assume that each sponsor provides an outstanding level of performance for the needs of that school.

Example -- If M1 fluids didn't hold up in those cars and resulted in failures that required very short OCI's, then surely Bondurant would use a more robust fluid to keep their operating costs down because engine parts and down-time are more expensive than oil. They use M1, so we can assume it is good enough for their demanding service conditions.

 

[A_Harman]

40psi is on the low side of normal for an LSx engine, especially if it's running 15w50 oil. And at 70F ambient temp, nothing was going to be running very hot. In 2009, I ran my Camaro for a combined 3 hours over two days at Buttonwillow raceway in 107F heat. This was on Mobil 1 5w30. Due to the high temperature, I was running the heater on full blast to keep the coolant temperature below 230F. Basically, I was driving the car according to the coolant temperature gauge. Once it got to 230F, I started shifting at 5000, instead of 5500, and began backing off early for the turns. By the end of the second day, the oil pressure while hot would not exceed 30psi, whereas normally it would be ~50. When I got home, I changed the oil and filter, and oil pressure returned to normal. I have driven the car ~30k miles since, and it seems OK.

 

[cronk]

Given the climate in Arizona and the hard driving conditions at a performance driving school, I think 15w50 is a great choice!

 

[jorton]

Originally Posted By: buster
Yeah the 15w50 could be making things worse actually.


15w-50, 5w-50, and 0w-40 don't list GM Service Fill Approvals.

 

[rpn453]

Originally Posted By: XS650
The C6 based Z06 doesn't need the thicker oil as much as the base model C6 and Z-51 C6
..
The Z06 has a big oil cooler and it's oil runs 25-40 degrees cooler then the others.


Thanks for the info. I'll take that into consideration and tell him about that, but I still lean toward having a high HTHS for hard use. I had recommended using 15w40.

 

[rpn453]

Originally Posted By: Matt_N
Having sat behind the wheel of a C6/Z51 for a 30min open lapping session on the Firebird West Course, I can tell you that oil pressure remained nearly constant at 40psi the entire time I drove the car. Temps were 70F there last week. I can't say that I think 15w-50 was hurting the cars.

My thoughts on sponsorship -- when you go through as much oil / brakes / tires / etc as that school does, you need to have sponsors just to offset the operating costs. While we can debate whether (or not) each sponsor is the absolute best in their field, we can also safely assume that each sponsor provides an outstanding level of performance for the needs of that school.


I agree on the sponsors. It's a great way to advertise because it demonstrates the product in hard use and it helps offset the costs for the user. It seems like a win-win to me. My instructor said that some students go through a full set of tires during the three-day course. A set of high-performance run-flats isn't cheap. I didn't mind being subsidized a bit.

I noticed they used the Michelin Pilot Sport PS2 on the ZR-1s there. I guess Goodyear doesn't make a tire that size?

I told myself to occasionally look at the gauges, at least on the straight, but I almost never did. It was hard to think that much when you're always in a race with three of your closest friends. I actually wonder if they shorted us a bit on track time because of high tightly we were bunching up. I expected a little more track time on the last Vette day. If one of us was alone, we'd slow and wait for the others to catch up. I preferred staying close to my friends to see where I was gaining or losing time, and whether I could keep up with them or lose them. We were all pretty close.

 

[buster]

I think the 0w40 would work very well.

 

[Steve S]

I could see 15w-50 being a very good choice.

 

[Steve S]

Originally Posted By: buster
I think the 0w40 would work very well.
The 0 part isn,t needed in this application.