Facts About Royal Purple 5W-20 XPR Racing Oil

[Cosmicdrifter]

I know that the subject of "which oil" is contentious, and I'm not here to make a comparison. All I wanted to do was clarify for some members a point that I was confused about - because of internet conflicts about the facts.

I bought some Royal Purple 5W-20 XPR Racing oil to use in my Cobra; then read on the internet (which we know is full of crap) that it was not to be used in street cars because it did not have to proper additives to fight acids and other harmful compounds created by short trips (whatever those are).

So the implication was it had to be changed frequently; I wanted the oil because it was recommended by many engine builders and has the additives to minimize cold start wear and spirited driving wear.

As a last resort I called the technical staff at Royal Purple, told them what kind of car I had and asked about whether it was appropriate for the engine. They said it DID have all the additives appropriate for street driving and the change intervals would be 10,000 to 12,000 miles.:rockon:

 

[Fat-cat]

i would still change it every 5 if you beat on the car allot. But i hear the RP stuff works great. Im a Mobil 1 User myself.

 

[GodStang]

I still change mine about every 100 miles.

 

[UnleashedBeast]

It's not that racing oils do not have TBN (total base number - detergent additives) in the oil, it's that there are lower amounts in most formulations that their street version of the oil. Can you use racing oil in your street car, of course you can. Should you normally run it at extended drain intervals like a dedicated street oil, I wouldn't recommend that.

It seems that Royal Purple is simply adding more anti-wear and pressure additives to their street oil and calling it XPR. That would explain why it has the same drain interval capacity as their street oils.

Amsoil Dominator racing oils do have less TBN than their street oils, but that doesn't mean you can't use it on the street. It just means you don't want to run it as long. Why would a formulator want to waste valuable detergent additives in a racing lubricant when they know the end user will be dumping the oil long before it is due? That's the reason they are normally formulated with lower TBN content. Royal Purple appears to be the exception to the rule, although....they do not list TBN content in their product data sheets anywhere on their website.

Amsoil also doesn't list TBN on their Dominator racing oils.

 

[Bdubbs]

I still change mine about every 100 miles.

op:

 

[x NOODLES x]

I still change mine about every 100 miles.

Or every 2 years. Whichever is comes first right? :lol:

 

[UnleashedBeast]

Here is a UOA of Amsoil Dominator 15W-50 after three weekends of circle track racing.

It still had TBN readings of 7.43, and this means in a street car....you have a lot of usable additive remaining in the oil (1.0 or lower is critical level). The virgin content was probably about 8 to 8.5 IIRC. IMO, when used in a street car, this lubricant would be good for a 10,000 mile change interval.

*Ignore the flagged lead ppm content. That's due to leaded race fuel, not an internal engine failure.*

For comparison with Amsoil top tier street oils, they have 11.5-13.1 TBN content.

IIRC, Royal Purple street oils have 8 to 9 TBN content, which is about the same as RP and Amsoil racing lubricants.

 

[cbr repsol]

totally off topic but unleashedbeast that chick in your sig is smoking hot.

 

[Bdubbs]

totally off topic but unleashedbeast that chick in your sig is smoking hot.

I agree I've found myself staring at it quite a bit, hope my wife doesn't catch me staring.

 

[jrgoffin]

Adding to all this, the racing oils also have higher levels of Phosphorus and Zinc in them, which is supposedly not as conducive to longer catalyst life. The new SM standard has the Zinc & Phosphorus levels limited to 0.9% and 0.8% respectively which translates to 900ppm & 800ppm.

As an example, the M1 5w30 has the Zn & P levels of 900 & 800, whereas their Racing 0w30 has them at 1850 & 1750. Not sure about RP, but many of the top of the line synthetics (Amsoil, Redline, etc.) have those levels up around 1500+ as well.

 

[RAPTOR5V]

totally off topic but unleashedbeast that chick in your sig is smoking hot.

bitch is a porn star - talk about frequent oil changes

 

[RTCOBRA2964]

totally off topic but unleashedbeast that chick in your sig is smoking hot.

X3 epper:

 

[Jimmysidecarr]

The R/P racing oil is pretty expensive, so I run 1/2 street and 1/2 racing in a Canton road race pan. It's a fairly expensive fill, but not as expensive as all XP.

I am also not a fan of 20wt oil, at least not for my usage. It will make more power with 20 weight in it, but my usage is pretty close to endurance racing with mostly street driving tossed in on top. Money isn't my main reason but it's part of it, I like having a blend of those two oils for my usage.

I'm running the 10w40 weight and I have not had any lash adjuster issues or any oil related issues AT ALL. If they made a 5w40 or a 0w40 I would run that. In Houston I'm not too worried about a 10 cold side rating.

My stock cats are still fine... bla bla bla.

If I was not doing open track events I would be running the 5w30.

If I wanted to make the most possible horsepower and get the best gas possible mileage I would run the 5w20. But I don't.
I'm also making 146 horsepower more than when I was stock, so I'm thinking I modded the power output I'm going to mod the oil protection too. So no 20wt for me.

 

[03cobra#694]

Wow, a actual interesting oil thread.

 

[cobracide]

Wow, a actual interesting oil thread.

Must be the chick.

 

[svt4me38]

must be the chick.

agreeeed!;-)

 

[03cobra#694]

Must be the chick.

lol :banana:

 

[MGC]

The R/P racing oil is pretty expensive, so I run 1/2 street and 1/2 racing in a Canton road race pan. It's a fairly expensive fill, but not as expensive as all XP.

I am also not a fan of 20wt oil, at least not for my usage. It will make more power with 20 weight in it, but my usage is pretty close to endurance racing with mostly street driving tossed in on top. Money isn't my main reason but it's part of it, I like having a blend of those two oils for my usage.

I'm running the 10w40 weight and I have not had any lash adjuster issues or any oil related issues AT ALL. If they made a 5w40 or a 0w40 I would run that. In Houston I'm not too worried about a 10 cold side rating.

My stock cats are still fine... bla bla bla.

If I was not doing open track events I would be running the 5w30.

If I wanted to make the most possible horsepower and get the best gas possible mileage I would run the 5w20. But I don't.
I'm also making 146 horsepower more than when I was stock, so I'm thinking I modded the power output I'm going to mod the oil protection too. So no 20wt for me.

Jimmy, will you explain why the 5w20 would make more power and why a thicker oil would be better for open tracking our cars?

 

[jrgoffin]

Thinner oil has less "drag" on the engine, so it theoretically will increase gas mileage (thus the change to the 20wt) and allow the engine to make more power. Don't get your hopes up on power increases, it is probably negligible.

As for the heavier oil, when it is run harder and longer, it will tend to shear to a thinner viscosity. Additionally, you are looking at much higher temps when you run at consistent higher RPM's, so the heavier oil will stand up. Most guys can and should run a 30wt for normal use but use a 40wt or even 50wt when racing.

There are a bunch of good oil threads in the GT500 forum, but is you want to learn the basics of oil, here is a good start (Bob is the Oil Guy):

Welcome

 

[MGC]

Thinner oil has less "drag" on the engine, so it theoretically will increase gas mileage (thus the change to the 20wt) and allow the engine to make more power. Don't get your hopes up on power increases, it is probably negligible.

As for the heavier oil, when it is run harder and longer, it will tend to shear to a thinner viscosity. Additionally, you are looking at much higher temps when you run at consistent higher RPM's, so the heavier oil will stand up. Most guys can and should run a 30wt for normal use but use a 40wt or even 50wt when racing.

There are a bunch of good oil threads in the GT500 forum, but is you want to learn the basics of oil, here is a good start (Bob is the Oil Guy):

Welcome

Thanks for explaining, that makes sense. One more question, I thought that heavier weight oil was "bad" for our cars because of the tolerances in our motors? Or is this one of those myths? Was 5w20 recommmended for gas mileage and emissions, or because of the tolerances?

I apologize if this subject has been beat to death already, just want to clear some stuff up and get the right information.


EDIT: I found this: http://forums.corner-carvers.com/showthread.php?t=36607

Which seems to answer my question, let me know if you agree or not.