Motor oil question for a race car

[OceanRocket24]

Hello again everyone!

I have a 1990 Acura Integra and I race in a four cylinder, absolutely stock racing series that races at my local dirt track. These cars are pushed their maximum potential. We usually run the car near or above 6,500 RPM through the whole 5 mile race. I have used 10W-40 of both Castrol Syntec and Mobil 1 High Mileage. More than the choice of oil, what weight do you think I should use. Most people have said that 10W-40 is sufficient and I have heard a couple 20W-50 suggestions as well. What do you think? Any other suggestions would be cool as well! Thanks for your time! The car ran great on both so far.

 

[sunfire]

You'll loose some HP running 20W-50. That's why NASCAR teams use the really thin oil during qualifying. 20W-50 is really for race cars that do 9-10K for many hours like in NASCAR.

 

[d00df00d]

I wouldn't go thicker than xw-40. You always want the oil to be as thin as possible, as thick as necessary.

 

[ARCOgraphite]

With oil temps under 125C, 3qts M1 HM 10w-30 and balance M1 R 4T. Can you tell us about the sump temps you are seeing?

 

[gathermewool]

What exactly is the determining factor here for oil weight? At high RPM, I'd think a lower visc would perform better. Is it the cyl wall to piston/ring interface that requires a higher visc?

I guess I just don't understand why a higher visc is recommended for high RPM running.


I can understand wanting a thicker film at high loads and low RPM, but what about high visc is beneficial as the RPMs go up, assuming same base oil and add pack?

 

[d00df00d]

Temperatures. High RPM means high temps, which means the oil thins out, which means oil pressure drops. Thicker oil is one way to compensate.

 

[Gator]

Interesting topic, since running a engine at high rpm's for extended time will certainly be a test of the oil. In my day we ran 20w50 oil in big blocks and I am sure there was alot of power left on the table but that was the oil everyone run. Even today I no guys who run drag cars with Big block on alcohol still running 20w50, only difference they will make sure the oil is at operating temp before making a pass. I beleive the upper limit on oil temp is 250, and like in nascar they have a huge oil tank and numerous coolers to keep the oil in the desired temp range so it will not break down, not sure that will be the case in any of the cars I have ever been around on dirt tracks.

 

[ryan2022]

I would continue to use Castrol GTX OR HM.

I've seen good UOA with these oils for track use.

Stick with the 10w40, you wont gain much at all going with the 50 weight in the integra.

 

[Johnny]

Is the only thing you do with the car is race it?

 

[lexus114]

Ok,I gotta mention it! What about using our beloved GC? or even Mobil-1 0W-40?

 

[Johnny]

Our? You got a mouse in your pocket?

 

[lipadj46]

or a 15w40/5w50 HDEO?

 

[DieselTech]

5-30 Redline

 

[Johnny]

Originally Posted By: Johnny
Is the only thing you do with the car is race it?


Since you stated you race this at your local dirt track I assume it has the interior knocked out, roll cage, etc., and you trailer it to the race track. If that is the case and racing is all you do with this car, I would use the following.

Red Line 30wt "RACING" Oil. Not the multi-vis street stuff, but their straight 30wt "RACING" Oil.

Ps: How about a picture of this dirt tracking Acura?

 

[DieselTech]

I agree with the straight weight redline....IF it is a trailered vehicle

 

[Johnny]

That's the key word here, IF.

 

[Ben99GT]

The thing is though, Red Line multi-vis street oils (10W-30, 5W-30, 5W-20) are really straight weight oils themselves. The straight 30-WT race oil is a 10W-30, with natural multi-grade properties.

The biggest difference between the street and race oils is that the race oil has almost double the ZDDP and fewer detergents (and TBN). Steve Millen is using the 0W-40 street oil in his Nissan GTR rally car: http://www.redlineoil.com/news_article.aspx?id=9

I'd go with a Redline street oil (5W-30, 0W-40, 5W-40, 10W-40) personally.

 

[Johnny]

That is all and good, but if you really want a lot, and I mean a lot of ester content, the straight weight racing oils have a higher content. Just call old Dave at Red Line. If I were JUST racing, and only racing, I would use one of their racing oils. I've seen to many high end motors torn down not to change my opinion on this. Now if this is just an old beater being raced on Saturday night for fun, heck, stick with what ever he is doing know.

 

[ThirdeYe]

So this is a stock B18 motor that's just being pushed hard, correct? Never thought I'd see an Integra being off-roaded. I don't race mine so I'm not sure what to recommend but I do like to drive it hard from time to time, seeing some redline shifts, high speeds and quick acceleration and 30 grades seem to hold up just fine. I was gonna try Mobil 1 0W-40 sometime even though my motor seems to prefer the thinner end of the 30-grade spectrum (like Castrol Edge and Havoline DS). Personally I don't think you need to go higher than a 40-grade.

 

[Ben99GT]

Originally Posted By: Johnny
That is all and good, but if you really want a lot, and I mean a lot of ester content, the straight weight racing oils have a higher content. Just call old Dave at Red Line. If I were JUST racing, and only racing, I would use one of their racing oils. I've seen to many high end motors torn down not to change my opinion on this. Now if this is just an old beater being raced on Saturday night for fun, heck, stick with what ever he is doing know.


The way I see it, if the 0W-40 street oil is good enough for Stillen Motorsport's 500 HP turbocharged Nissan GT-R in a 1370 mile rally race, it's MORE than good enough for this Acura.

I've never heard of RL's race oils having higher ester content than their street oils, but I just sent Dave at RL an e-mail asking him about this. In fact, I've always understood that Redline uses the optimum amount of POE for the desired seal swell/polarity characteristics, cutting it with PAO (used as their additive carrier) to keep it in check.

If Dave replies that the race oil has a higher ester content, I will be surprised. All the more surprised considering their race oils and the street oils are roughly the same price.