Determining oil to use for autoX/Daily driver

[bcredeur97]

Hello! I have a 2002 Mazda Miata that I currently use as a daily as well as an autocross car 9 months out of the year, once a month. Usually 6-12 90 second runs, as our courses are pretty lengthy and I often have a co-driver.

Now most people consider autocross to be rather light and not too hard on the car, but our courses are typically a bit longer than most, and the car doesn't always get a big break in between runs so I'm sure temps start creeping up pretty high. Miata's are known to run very high oil temps, even like 250F in traffic. I don't have an oil temp sensor on mine but I could imagine on a 4th session in a row at an autoX those temps are pretty high...

Now I've been using Mobil 1 0w-40 magical sauce in it, and it seems to have a decent result. But I'd feel better with something heavier for 5k mile changes. Like a 0w-50 or 0w-60 if that even exists lol

But that may not be necessary. Should I change my oil in shorter intervals? The miata only holds 3.8 quarts as well so oil changes aren't exactly expensive(though they are kind of a pain with the filter location) My main concern is the intense heat combined with high rpm operation that could shorten lifespan for sure with oil that's too thin.

And what oil would you use in this situation and why? I'm interested in opinions.

 

[JoelB]

Redline runs "heavy" for it's grade. If i was running my daily like you are I'd probably run their 5w-40. But I'm probably biased as I've always wanted to use Redline but have never had a reason.

 

[Inspecktor]

Mobil1 0W-40 will work fine. If oil temps concern you, install an oil cooler.

 

[Linctex]

Originally Posted By: bcredeur97


Now I've been using Mobil 1 0w-40 magical sauce in it, and it seems to have a decent result. But I'd feel better with something heavier for 5k mile changes. Like a 0w-50 or 0w-60 if that even exists lol


5W-50 is available

 

[bcredeur97]

Originally Posted By: JoelB
Redline runs "heavy" for it's grade. If i was running my daily like you are I'd probably run their 5w-40. But I'm probably biased as I've always wanted to use Redline but have never had a reason.

I've never tried any of their products before. But they seem to make good stuff. Whatever makes this engine last as long as it can...

Originally Posted By: Inspecktor
Mobil1 0W-40 will work fine. If oil temps concern you, install an oil cooler.

Actually can't do this because of SCCA stock class limitations... And I wish to remain in the stock class.

Originally Posted By: Linctex
5W-50 is available


Really? hmmm... might be worth using that.


Is there anything I could add to the oil to help? Any additives like moly or that ceratec stuff liquimoly makes? or are is the general consensus on adding things to oil "a bad idea"?

 

[09_GXP]

Road racers use 30wt oil with no problems or oil life concerns. I would run 30wt and nothing heavier to save some power. Stick with the M1 0w40 if it makes you feel good but there is no reason to run heavier.

I run Redline Race 30wt (very light 30) in my 2009 Road Race Miata and PP 0w20 in my 2017 autocross Miata RF.

 

[BrocLuno]

IIRC - Castrol makes a 10W-60 RS full synthetic as a race oil in Europe ... I still have a few bottles in my stash.

You might look at Motul 300V and their line up ... But, as stated, there are some well known Red Line oils that run in S2000's and Miatas that are AutoX'd

 

[bcredeur97]

Originally Posted By: BrocLuno
IIRC - Castrol makes a 10W-60 RS full synthetic as a race oil in Europe ... I still have a few bottles in my stash.

You might look at Motul 300V and their line up ... But, as stated, there are some well known Red Line oils that run in S2000's and Miatas that are AutoX'd

eh I've always felt "race oil" is made for the track. I don't think you should run that in a daily, even if it sees occasional track use, unless maybe you changed the oil just for the track.

Redline seems to be an everyday street-car oil though... but they do have their race-specific oils. Just as good as UOA's are on the Mobil 1 stuff is, I probably shouldn't switch. Maybe just change oil every 3k miles or so if I'm paranoid.

 

[raytseng]

Just change more frequently. if the filter is a pain, then change that less frequently. You'll need to get an UOA to be sure.

I suppose just take another 60 seconds to take a cool down lap would be helpful.

In my opinion, I think oil is least of your worries, brakes and tires probably more important to focus on.

 

[FlyPenFly]

Personally in Louisiana, in a hot engine, I would run a 10w40 from Redline. They have the lowest NOACK % and some of the highest HTHS specs of anyone. At the least, IMO, I would switch to Castrol 0w40 considering how quickly M1 0w40 seems to sheer down in demanding applications.