Oil for NC MX-5 Miata track/autocross car

Status
Not open for further replies.
Joined
Aug 29, 2017
Messages
9
Location
Texas
I recently bought a 2013 MX-5 Miata. It's naturally aspirated, and has a stock motor with 61K miles on it. I'm looking for an oil recommendation for predominately track and autocross use.

Street driving is limited to driving to and from motorsports events. I expect annual mileage to be no more than 6K miles per year. Despite the low mileage, I plan to change the oil at least twice a year, maybe more, mainly because a large percentage of the miles will be accumulated under high-temperature hard-driving conditions.

Mazda specifies a 0w20 oil for this car. I want to stick with that viscosity. The previous owner exclusively used Motul 8100 ECO-lite full synthetic 0w20 oil. It's expensive at about $18 a quart. I'm looking for something less costly that will be well-suited to my planned use and oil change interval.

I appreciate any suggestions you might have, and any insights you could share about picking the right oil for a given use.
 
If you really want to stick with 0w-20, I would go with Red Line. It's also expensive at @12.50/quart, but it has a NOACK of 9.
 
NOACK = a test procedure for measuring volatility

Thanks glock19. I had to look up NOACK in the glossary/acronym thread. Now I'll have to spend some time understanding what the numerical value means. Where could I find that number for other oils, like the Motol 8100 ECO-lite oil, for comparison purposes?

The reason I want to stick with a 0w20 is partly because that is what Mazda recommends. But also because I'd read elsewhere that increasing the viscosity of the oil will result in higher oil pressures to maintain the flow of oil to all parts of the engine, and it may cause higher oil temperatures, and churn as the oil pump's bypass valve opens and dumps oil into the sump. So less oil is being used to lubricate.

But I do not know how truthful that is. I figured I'd start studying the topic, but maintain the manufacturer's recommended oil type and viscosity until I understand a lot more about it.
 
My understanding is that the first number, 5w vs 0w, affects lubrication at cold startup, with the lower weight oil providing better lubrication when the engine is cold, and having little to no effect at hot-running temperature.

Are there other factors or properties of a 5w oil that would make it a better choice than 0w for track/autocross where the majority of the time is spent at high oil temperature?
 
I run Redline 30wt Race oil in my NC that is stock with "only" a tune to run 100 octane street legal fuel. The car seems to love Redline fluids so if you want to stick with 20wt I'd go with Redline 0w20. It will keep the same viscosity but it does have a higher HTHS for protection.
 
Originally Posted By: trackit
I recently bought a 2013 MX-5 Miata. It's naturally aspirated, and has a stock motor with 61K miles on it. I'm looking for an oil recommendation for predominately track and autocross use.

Street driving is limited to driving to and from motorsports events. I expect annual mileage to be no more than 6K miles per year. Despite the low mileage, I plan to change the oil at least twice a year, maybe more, mainly because a large percentage of the miles will be accumulated under high-temperature hard-driving conditions.

Mazda specifies a 0w20 oil for this car. I want to stick with that viscosity. The previous owner exclusively used Motul 8100 ECO-lite full synthetic 0w20 oil. It's expensive at about $18 a quart. I'm looking for something less costly that will be well-suited to my planned use and oil change interval.

I appreciate any suggestions you might have, and any insights you could share about picking the right oil for a given use.



How many track events do you plan on doing per year? Autocross isn't particularly hard on oil since the runs are so quick and don't involve sustained periods of WOT. I wouldn't alter the oil type or schedule for autocross unless you are doing it every weekend for multiple months out of the year. Track days will work the motor much harder since it's 15-20 minutes of sustained WOT 5-6 times in a given day.

Something like Red Line 0w20, as others have said, might work. I would run it for half the race season, pull a sample for analysis, and see how it is holding up. Be sure to pay for TAN & TBN as those will be good metrics for the change interval.
 
Run at least 5W-30 or 0W-40 M1 if you're going to track it. That lightweight stuff is for fuel economy, not WOT high RPM work.
 
Originally Posted By: 09_GXP
I run Redline 30wt Race oil in my NC that is stock with "only" a tune to run 100 octane street legal fuel. The car seems to love Redline fluids so if you want to stick with 20wt I'd go with Redline 0w20. It will keep the same viscosity rating, but it does have a higher HTHS for protection.


^^^^ This
smile.gif


Is nearly shear proof and can handle heat
smile.gif


I would not change it just because ... Run it 6 months at events and then sample the oil, send it in for analysis. Based on what they find, change or not. Maybe spin on a new filter and top up.

Make sure you run magnetic drain plug. You want to see any Fe fuzz that the engine is throwing off ...

You want the highest HTHS 20 you can find. I'll bet Redline is close to it. Motul is great oil, but their ECO fluids are thin. Not what you want at temp and at redline on the tack at full throttle ...
 
Originally Posted By: dparm

How many track events do you plan on doing per year? Autocross isn't particularly hard on oil since the runs are so quick and don't involve sustained periods of WOT. I wouldn't alter the oil type or schedule for autocross unless you are doing it every weekend for multiple months out of the year. Track days will work the motor much harder since it's 15-20 minutes of sustained WOT 5-6 times in a given day.

Something like Red Line 0w20, as others have said, might work. I would run it for half the race season, pull a sample for analysis, and see how it is holding up. Be sure to pay for TAN & TBN as those will be good metrics for the change interval.


Autocross is nearly all year long here in the DFW area. Four autocross clubs, about 45 events per year, sometimes two per weekend. I'm going to Lincoln for SCCA Solo Nationals next week.

I've done 11 track events so far this year, with 4 more scheduled through the end of the year, and one tentative. SCCA Club Trials, HDPE's, and TNiAs. No racing. I got to run COTA for the first time yesterday with Track Night in America. That was fun.

Thank you for the oil analysis recommendation.
 
Originally Posted By: BrocLuno

I would not change it just because ... Run it 6 months at events and then sample the oil, send it in for analysis. Based on what they find, change or not. Maybe spin on a new filter and top up.

Make sure you run magnetic drain plug. You want to see any Fe fuzz that the engine is throwing off ...

You want the highest HTHS 20 you can find. I'll bet Redline is close to it. Motul is great oil, but their ECO fluids are thin. Not what you want at temp and at redline on the tack at full throttle ...


Thank you.

Motul 8100 ECO-lite lists the HTHS viscosity at 150C at 2.7 mPa.s, no specification for NOACK.
Redline 0w20 lists HTHS viscosity at 150C as 2.9, NOACK 9
Redline 5w20 lists HTHS viscosity at 150c as 3.0, NOACK 8

Now time for me to study what that really means.
smile.gif
 
What it really means is the higher the HTHS (high tempurature high shear [resistance]), the better. In any chosen grade range, for motors that will spin and run hard, the highest HTHS is always the best
smile.gif


I'd take the 5W-20 in that group you show
smile.gif
 
Thanks BrocLuno. I'll start with that, and pull a sample for analysis in 6 months.

And thanks to all of the rest of you for your explanations and suggestions.
 
Last edited:
What are the implications in terms of engine protection and lubrication qualities, especially for high RPM and high-operating temperature use, of the slightly different viscosity numbers of the RL 5W20 vs 0W20 oils? The numerical differences are very small.

RL 5w20

ACEA Service Class A5 B5
API Service Class SN/SM/SL/CF
SAE Viscosity Grade (Motor Oil) 5W20
Vis @ 100°C, cSt 9.0
Vis @ 40°C, cSt 53
Viscosity Index 147
CCS Viscosity, Poise, @ °C 60@-30
Pour Point, °C -45
Pour Point, °F -49
NOACK Evaporation Loss,1hr @ 482°F (250°C), % 8
HTHS Vis, cP @150°C, ASTM D4741 3.0


RL 0w20

ACEA Service Class A5 B5
API Service Class SN/SM/SL/SG/CF
SAE Viscosity Grade (Motor Oil) 0W20
Vis @ 100°C, cSt 9.1
Vis @ 40°C, cSt 48
Viscosity Index 172
CCS Viscosity, Poise, @ °C 55@-35
Pour Point, °C -60
Pour Point, °F -76
NOACK Evaporation Loss,1hr @ 482°F (250°C), % 9
HTHS Vis, cP @150°C, ASTM D4741 2.9


And as an aside, if I look back through posts from a few years ago, I see that the HTHS vis @150C for RL 5w20 was 3.3, whereas now it is listed as 3.0. Why such a big change over a few years time?
 
Interesting that the HTHS for RL 5W20 was 3.3 a few years back, that is higher than most 5W30s I have looked at. Not sure why it changed...

My take is that the very cold temp properties of the 0W20 mean next to nothing to you in Texas.
The slightly higher HTHS of the 5W20 means a slightly higher minimum oil film thickness for better protection if your engine gets extremely hot, and its slightly lower NOACK means slightly lower nasty engine deposit potential for the same condition. Unless you are dead set on 0W20 due to Mazda's recommendation (and I'd guess that they also recommended an SN oil, which Redline is not), I think that 5W20 suits your needs a little better.
 
Thank you, Virtus_Probi.

I decided on the Redline 5w-20. I should have a case on my doorstep by the time I get home tonight.

The owner's manual for my 2013 MX-5 specifies 0w-20 labeled with an API symbol and ILSAC GF-4/GF-5 for the US and Canada. There is no mention of an API Service Class. For Mexico, it specifies 5w-20 and either API Service SM, or ILSAC certification, and it also says that 5w-30 can be used if 5w-20 is not available.

I also have a 2015 MX-5, which is the last of the NC generation. It has the exact same MZR 2.0L engine as my 2013, and the oil specification is the same, except that it mentions ILSAC, but not GF-4/GF-5.

Redline 0w-20 and 5w-20 are both API Service Class SN, according to the data I posted above from the Redline website. Maybe the change from SM to SN had something to do with the HTHS vis change?
 
Originally Posted By: trackit
Thank you, Virtus_Probi.

I decided on the Redline 5w-20. I should have a case on my doorstep by the time I get home tonight.

The owner's manual for my 2013 MX-5 specifies 0w-20 labeled with an API symbol and ILSAC GF-4/GF-5 for the US and Canada. There is no mention of an API Service Class. For Mexico, it specifies 5w-20 and either API Service SM, or ILSAC certification, and it also says that 5w-30 can be used if 5w-20 is not available.

I also have a 2015 MX-5, which is the last of the NC generation. It has the exact same MZR 2.0L engine as my 2013, and the oil specification is the same, except that it mentions ILSAC, but not GF-4/GF-5.

Redline 0w-20 and 5w-20 are both API Service Class SN, according to the data I posted above from the Redline website. Maybe the change from SM to SN had something to do with the HTHS vis change?


You are most welcome!
However, I don't believe that Redline is actually API certified...note the the website says "recommended for" and "suitable replacement for" things like API SN. You may find different when you see the bottles delivered and please correct me if I am wrong on this point.
The common thought that is expressed here is that Redline users don't really care about things like API SN and would probably be disappointed if it actually met such specs!
 
Here's an article I saved, from MX5miata.net, from member AussieMX5, posted October 2006. Enjoy.



A little something to set the cat amongst the pigeons

--------------------------------------------------------------------------------

There has been a few posts regarding oils/fluid lately and Mazda's recommedations so I have decided to share some info past on to me by one of Mazda Japans more senior engineers.

I had the luck of meeting him a couple of years back while he was in Aus. He heads here a couple times a year to help in the process of changing model ranges to meet Australian standards and enviromental considerations (fuel quality, roads, weather etc). We met because of a demonically possesed (well thats all I can attribute it to) RX8 that just had so many engine, electronic, gearbox and even interior fit and finish issues Mazda Aus was throwing their collective arms in the air. While he was in the country they bought him in to take a look at the car. It was from his input that I was fully refunded the cost of my RX8 and offered the MX5 at cost.

To his credit he did the very Japanese thing and felt it was important that he meet and apologise to me on behalf of Mazda Japan. He really did seem embarressed by the cars failures.

It was from here that we struck up a friendship. Had a few dinners, even took him out on one of my track days where he spent a fair portion of the day in my mx5 driving around one of our more famous circuits with a couple of our top racing drivers beside him improving his skills!

During this time the question of oils came up. I asked what would be best to look after my NC considering the use it gets. His response was the Mazda specifications are a compromise between protection and economics and through the use of better oils and revised changing intervals you can give the car far better protection. If Mazda increased their recommendations for oils and servicing to meet the ultimate level of protection then they would lose sales due to the servicing costs. In a nutshell Mazda's recommendations offers the best protection for a certain budget level.

Together we came up with a plan for my NC based on my useage and his knowledge/experience.

Engine oil: I now run Castrol Edge fully synthetic 10w-60 (was Castrol R until they changed the name). This oil is thin enough for cold start in aus climate but offers increased protection for constant high rev use and high heat applications. His words were a great oil for any NC that see's track days. Looking at the oil after seeing similiar track time to my previous dealer installed synthetic 10w-30 and it looked a heck of a lot better after being drained out compared to what was left of the 10w-30.

Gearbox: this is the one that will get some negative feedback by forum members but again is on his recommendation - Redline lightweight shockproof. I was unsure of this as I have read the posts about it and also read the Redline material that does not recommend it for Syncro type transmissions. The real problem he explained is in transmissions that use small underpowered pumps to circulate the oil around the gearbox and that because of the way this oil is attracted to metal it will sometimes block these low powered pumps (The Subaru STI is a classic example of this he stated). As Redline cannot test in all non race Syncro type gearboxes the earlier statement is easiest. Also because of its thin nature should be changed more frequently to keep maximum protection and avoid deterioration. I have to say after putting it in my gearbox the difference in feel is stunning. The gearchange is like a hot knife through butter and no issues with 2nd and 3rd I had been having (The occasional difficulty of getting it to go into gear & grinding when this happened) The car also feels smoother and seems to rev out a little easier above 5000rpm. The driveline clatter has also been reduced at low rpm or in neutral.Although he did suggest you drive it a little gently for the first couple hundred km's just to let it fully settle in.

Diff: Again the Redline Lightweight Shockproof. Things seem smoother again and it does feel as though I do get better drive out of tight corners although that is something very hard to measure.

Change intervals: He recommended I change the engine oil and filter every 5000km because of the track work. If I was not doing track time he recommends oil change every 10,000km and a filter change every 5000km. For maximum protection I was told more frequent filter changes were better that changing a good synthetic oil all the time as a good synthetic will handle the 10,000 interval. For the gearbox and diff I change every 20,000km again because of the track work and also this keeps the lightweigh shockproof in the sweetspot for maximum protection!

Well thats it. On this regime I have to say my NC runs truly brilliant and it performs smoothly enough that the Mazda mechanic who performs the services has commented on that. At the last dyno day with 3 other NC's all on the same dyno within the space of 45 minutes before lunch (mine last) my NC scored 94.6kw at the wheels while the other 3 were 90-92 at the wheels with the only difference being beside my oils and track days, I am on JIC's they are on the Eibach springs and all on the same tyres. Judging by the figures and feel my NC seems pretty happy!

I should not say anything but just for a little tease last month while he was out here working with a team from Mazda and a very well known organisation I cannot divulge, he invited me to have a small test drive out at Broadford Motorcycle complex of an NC MX5 they are building to compete in Tarmac rallies around Australia. I promised not to say too much but from what I experienced Mazda will not be putting the MPS3/6 2.3l in the NC any time soon. Scary fast and without massive electronic nannies built in or serious de-tuning I think a lot of people would kill themselves in it on the roads! That's about as much as I can say on that

Cheers

_________________________
Old enough to know better, gettin' past too young to care. Darn it!
 
Thanks for that, olddognewtrks. It bears looking into. I'm using Redline transmission and gear oil, but not the Lightweight Shockproof. The 10w60 engine oil weight recommendation is most surprising. I have seen posts on miata.net from an engine builder saying that anything heavier than 20 weight (Xw-20) is a bad idea for the MZR 2.0 liter engine because of the tight tolerances. A Mazda engineer's opinion carries a little more weight, though, in my mind.
 
Status
Not open for further replies.
Back
Top