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What race oil should I be running?

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Hello everyone,

I have a HPDE event coming up and I'm trying to figure out what oil to run. The event will be occurring in Texas during the month of July. It's going to be hot. Ambient temp will probably be in the neighborhood of 105. I used Redline 30 weight race oil for my last event but that was in December with much cooler temps. I'm installing a Setrab 925 so that will help, but I was thinking about using a 40 or 50 weight oil this time around. What are your thoughts on this? Is there a better oil than Redline that I should use? Do any of yall have experience with Joe Gibbs racing oil? Any input would be appreciated. Thanks.
 

ArizonaBOSS

Because racecar.
Moderator
8,730
2,734
Arizona, USA
40 or 50 weight for sure, as the oils will lose some viscosity as the heat increases. FWIW on brand I either run Motorcraft or Castrol Edge in my race car. As long as it's full synthetic it should hold up to high-temperature use well. 5W-50 here.
 
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Ford suggests 5w50 in the manual for the 302S racecars. Any of the popular choices in 5w50 should foot the bill. Driven uses a different base oil that has a better VI that does not depend on friction modifiers. I think if you are using a good 5w50 and changing it often, you are going to be in great shape...
 
If ArizonaBOSS is running motorcraft 5w-50, I wouldn't have any doubt's running that.

The driven 5w-50 is like $12Qt or about $130 for a case of 12. plus the ford racing filter makes it a $150 oil change.

OP Mustang has a complete oil change kit for $99 for 9Qts of 5w-50, and the ford racing filter. (cheaper with less oil, and the regular ford filter)

https://www.opmustang.com/store/p19..._-_Lucas_High_Performance_Oil_Change_Kit.html
 

Grant 302

basic and well known psychic
Any decent 5W50 full synthetic, such as Motorcraft, Castrol, Mobil, etcetera.

Mobil One is on sale at Napa currently.

That's what I generally use, and hard to beat for the $5.99 sale price.

https://www.napaonline.com/en/p/MCL122075

I'd stick with at least a 50 wt in temps above 95º. Anything lighter and I would definitely dump it after a day of track use...and watch your pressure while using it.
 
This is probably a dumb question but what about 15w50? It just seems like 5w50 would shear pretty fast once it got hot. I have read that running 15w50 can cause problems with the variable valve timing system on the Coyote though since it's dependent on pressurized oil to operate and that the more viscous oil might not be able to traverse all the little passages it needs to in order to operate the VVT properly. This makes sense but I wanted to verify with some more experienced folks.
 
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The Coyote VVT is designed to operate properly independent of varying oil pressure. Unlike most VVTs, that require high oil pressure, the BorgWarner system in the Coyote does not use oil pressure to change the cam timing. The oil is used to create hydrostatic locks that either allow or prevent the cams from moving. Energy from the camshaft rotation and valve spring actuation are used to change cam timing. There is another thread on the board somewhere where I posted how the system operates.
 
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This is probably a dumb question but what about 15w50? It just seems like 5w50 would shear pretty fast once it got hot. I have read that running 15w50 can cause problems with the variable valve timing system on the Coyote though since it's dependent on pressurized oil to operate and that the more viscous oil might not be able to traverse all the little passages it needs to in order to operate the VVT properly. This makes sense but I wanted to verify with some more experienced folks.
Not a dumb question. Both 5w50 and 15w50 fall in the same Viscosity range when measured hot.

Whether or not or actually how much an oil will shear depends on a lot of variables and not just the specified viscocity. Here is a simple way to help understand this(at least to me).

Viscosity Index is a “score” that indicates an oil that will keep it’s abilty to sustain the protective barrier between metal parts in high heat scenarios. The higher the number, the better. Most 5w50 oils score I. The high 170 to mid 180 range; all very good.

Now this is where it gets tricky because one can make a lot of assumptions based on looking at VI alone.

VI can be raised by adding Viscosity improvers but these improvers actually wear out over time and will shear down over time (oil gets thinner) as it gets exposed to heat “cycles” that are normally sustained during on track driving.

If the oil is formulated with a really good base oil that naturally has a high Viscosity index before adding Viscosity improvers, it will resist shearing down and maintain its intended Viscosity.

Brands that use ester based “base” oil, are mostly PAO or even better mPAO base oil are going to have a high VI.

If you are changing oil frequently, as stated in this thread, shearing should not be one of you concerns.

Your VVT is going to work fine but it will not be running “optimal” if you go outside of OEM suggested Viscosity. “Optimal” being the key word.
 

Grant 302

basic and well known psychic
This is probably a dumb question but what about 15w50? It just seems like 5w50 would shear pretty fast once it got hot. I have read that running 15w50 can cause problems with the variable valve timing system on the Coyote though since it's dependent on pressurized oil to operate and that the more viscous oil might not be able to traverse all the little passages it needs to in order to operate the VVT properly. This makes sense but I wanted to verify with some more experienced folks.

Regarding shear, it depends on the 5W-50 you're talking about. MC and M1 hold up okay and test fine at 4 hours of run time.

If you're concerned about shear, there's no problem running 15W-50 that I've seen, but I only did that for one fill and didn't test afterwards. I'd just give it a bit more warm up time if you use it.
 
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Regarding shear, it depends on the 5W-50 you're talking about. MC and M1 hold up okay and test fine at 4 hours of run time.

If you're concerned about shear, there's no problem running 15W-50 that I've seen, but I only did that for one fill and didn't test afterwards. I'd just give it a bit more warm up time if you use it.
I would add that if shear is concern to go with a shear stable 5w50 vs Increasing Viscosity to a 15w50. Depending on the oil, you may just be adding drag and not increasing protection....
 

Grant 302

basic and well known psychic
I would add that if shear is concern to go with a shear stable 5w50 vs Increasing Viscosity to a 15w50.

Without getting into brand and formulation arguments, assume I mean for a given brand and similar formulation or base.

Depending on the oil, you may just be adding drag and not increasing protection....
Assuming all or any XW-50 oils, where would the extra 'drag' come from at operating temps?
 
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Without getting into brand and formulation arguments, assume I mean for a given brand and similar formulation or base.

Assuming all or any XW-50 oils, where would the extra 'drag' come from at operating temps?
The drag would come from the fact that 15w50 is actually thicker than 5w50. You are 100% corrcet, the both fall within the same range at temp but the two oils (15w50 vs. 5w50) will be one opposite sides of the 50 range? Make sense? BTW, I’m totally nit-picking the difference and the increase of drag would be negligible. I’m just nerdy about oil specs.
 
1,289
1,113
Exp. Type
HPDE
Exp. Level
5-10 Years
Philly Metro Area
Your VVT is going to work fine but it will not be running “optimal” if you go outside of OEM suggested Viscosity. “Optimal” being the key word.

What about non-Boss, non-Track Pack Coyotes that were spec'd to run 5W-20 but are now being used at HPDE Track Days/Nights? Will running anything other than 5W-20 result in non-optimal VVT? If so, is there anything that can be done about that? I assume that oil type for track use is much more important than any degradation of VVT performance.

I have a 2014 and I've been running 5W-30 in the winter off-season and 10W-40 during track season. Royal Purple HPS for both.

BTW, I'm in the NE US and won't run in ambient temps above 90°. And running Setrab 925 cooler.
 
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In a nutshell,but not the end of the world, yes. The difference between non-track pack and track-pack/Boss cars Is the base calibration from the factory. The are ancillary support items on track-pack/boss cars but the vvt hardware is the same. The algorithms developed for each type of application (track-pack vs non track-pack) assumes the type of Viscosity oil that will be used. It’s a significant difference where using other than 5w50 on a Boss can effect the “loopieness” of the track key idle.

The cool thing is that you can get really good 5w20 oils that do a good job of protecting and maintaining an oil film while strongly resisting shear. Both Driven FR20 and Mobil 1 annual protection 5w20 would fit the bill. More expensive but worth the peace of mind.

FYI, NASCAR teams have been running 5W20 for decades now albeit they are using formulations that utilize mPAO base oils that cost more but maintain viscosity without shearing down.
 
1,289
1,113
Exp. Type
HPDE
Exp. Level
5-10 Years
Philly Metro Area
Thanks, but why would Ford spec 5W-50 if 5W-20 would suffice and the only difference is how the tune sets the idle?

I'm running a Mike Rousch 93 octane road course tune during HPDE. In all discussions on various forums, I don't recall seeing anything about oil type being a tune parameter. While most S197s on the track may be Bosses and TPs, I'm sure I'm not the only person that has modified their base GT for the track.

Should this be an issue discussed with a tuner?
 

JDee

Ancient Racer
1,797
2,001
Exp. Type
W2W Racing
Exp. Level
20+ Years
5 miles from Mosport
I had an online chat with Ford Performance tech about what would be the correct oil in an unmodified Gen2 (2015-2017) engine for HPDE type track usage with 20 minute sessions that never sees anything beyond redline. The tech guy said unequivocally 5W-20 that meets the Ford engine oil spec is the right oil for the Gen 2 engine for that type of use. He said basically be guided by what it says on your oil fill cap and mine says 5W-20.

Note keywords here: unmodified, Gen2 (2015-2017), HPDE, 20 minute sessions, never goes beyond redline, oil fill cap, Ford engine oil spec.
 

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