2009 Miata Race Car, M1 5w20

[09_GXP]

Well here is my first oil sample from a car I am racing with the SCCA. The previous owner had run Mobil 1 5w20 in the motor since that's what is spec'd on the cap. The car is stock except for a cold air intake and tune to run on 100 octane street legal fuel (unleaded). The previous owner mentioned that he cut race fuel with pump gas (93 octane) to reach 100 octane but didn't say it was leaded. Based on what I'm seeing here I would call it a safe assumption to assume the fuel was in fact leaded. I have reached out to the previous owner to confirm.

I'm estimating the usage to be around 700-1000 miles in race conditions only but can't know that for sure. I've spoken with a lot of people and there is a pretty even split on running 30wt vs 20wt since the motor is stock. I run in the Touring 4 class which really restricts horsepower so any little bit makes a difference.

I'm currently running Redline 30wt Race Oil with a M1 filter. I will get an oil sample from it when I change out but may go back down to 20wt for the Runoffs to get every last hp out of the motor.

 

[aquariuscsm]

Don't Miatas spec 10W30? Or so I'd thought.

 

[SatinSilver]

The Honda S2000 specs 10w30, maybe you're thinking of that car. I remember the service advisor also stating that it should be synthetic but not sure if that's correct or not.

 

[09_GXP]

Originally Posted By: aquariuscsm
Don't Miatas spec 10W30? Or so I'd thought.


The NA and NB Miatas called for 30wt but the newer NC (2005+) and ND (2016+) call for 5w20.

 

[tig1]

If your engine is still designed the same as the Ford Durateh, there is no lead in the crank, rod, or cam bearings. The crank and rod bearings are made of a bi-metal aluminum and silicon type of material.

 

[Eddie]

I would compare these results with other engines that are raced and not just the Mazdas. The results look terrible to me, which suggests that the oil is TOO thin for this application. Ed

 

[tig1]

I don't believe this oil is M1 5-20. Reason. M1 5-20 will have around 70-75 PPM of Moly, instead of the 218 PPM your report shows. Also Zinc and Phosp are too hih for M1 5-20 according to your UOA. Something is wrong with this. Perhaps B_S used the wrong oil for your UOA.

 

[09_GXP]

I agree the add pack doesn't look consistent with M1. I would bet the previous owner put some additive into the oil. Everyone is pretty secretive so I can't get an answer there.

It looks like the MZR and Duratec share quite a bit of history so no lead in the bearings wouldn't surprise me. The previous owner did email me back and said he mixed "a little" leaded race fuel with pump gas to get the octane up to 100.

I'm not too concerned with the wear numbers. The oil was run further than I am going to moving forward. It was Mobil 1 20wt vs Redline 30wt Race Oil that I'm running now. Realistically, this engine was beat on pretty hard and is still winning races so it can't be in too rough of shape.

 

[Garak]

Yes, the additive package doesn't seem right, and someone used leaded fuel in there, and probably more than a "little."

 

[Popsy]

Quick question, isn't the lead susceptible to destroy O2 sensors?
I recall a warning like that in the manual of one of my cars.

 

[Garak]

Yes, and I'm not sure how healthy it is for the cat, either.

 

[09_GXP]

Yeah, the O2 sensor typically isn't too happy with the leaded fuel. Something I will likely change out before failure. The car has the cats cut out so no worries there.

 

[dgunay]

I would definitely use w30. w20 is recommended in North America, but w30 anywhere else in the world. You can even try w40.

In fact, you don't need an O2 sensor. Since you always track your car, that means it always runs on open loop, and open loop eliminates the o2 sensor reading. In other words, your o2 sensor even doesn't work most of the time on track. Probably it just works when you're idling.

If you don't have A/F gauge (with the sensor) so just tune your car with the OE primary o2 (assuming it's a wideband sensor), don't forget to tune low rpm-low load cells when you tune it, then take it out and save some money.

 

[nickolas84]

Racing a stock engine and putting more viscous oil than it is designed for? To me this sounds a sure way to have overheating issues. Modern engines are really well designed to take whatever is thrown at them, but putting a more viscous oil puts them out of spec and you could run into trouble.

I would suggest you keep to the stock spec for oil. If 5W-20 is specified maybe you can also use 0W-20, as these tend to be newer (and more expensive) formulations, although for racing the benefits may be really minimal.

Racing puts a lot of stress and if I were to throw a number, prolonged racing puts a 20x stress to the engine oil compared to normal in terms of distance. So try to change your oil every 1000 miles between racing events. Your oil calculator should also count for that.
Having said that, your aluminum value does not seem to be out of order, but you should revisit that at least once more with another oil report.

 

[dgunay]

Originally Posted By: nickolas84
Racing a stock engine and putting more viscous oil than it is designed for? To me this sounds a sure way to have overheating issues. Modern engines are really well designed to take whatever is thrown at them, but putting a more viscous oil puts them out of spec and you could run into trouble.

I would suggest you keep to the stock spec for oil. If 5W-20 is specified maybe you can also use 0W-20, as these tend to be newer (and more expensive) formulations, although for racing the benefits may be really minimal.


No. Unless you have cooling problems, your car won't overheat because of thicker viscosity.

It's better to switch slightly thicker oil (for track and autox) in order to keep the oil pressure high, at high temperatures. Mazda North America recommends xw20 for all Mazda's because of CAFE (emission) standards, but in fact it's recommended xw30 globally. No doubt that w20 grade is great for daily driving purposes, not suitable for long-term high load/high rpm applications.

If I were the OP, I would try 30 grade (maybe German Castrol 0w30?) and I would definitely get oil pressure - oil temperature gauges to see what's going on.

 

[nickolas84]

Are you sure? Even with 40C outside temperature? dgunay I see you are from Canada and as a matter of fact I realize now that the OP is from Indianapolis so it may not be a real problem for him either. In hot weather my experience is that modern engines can get close to 130C oil temp if you keep the pressure without a cool down lap. Putting a thicker oil could easily make them exceed 140C because at this point the cooling system is already maxed out. But then you are in the red zone.

There could be other reasons 0-30 is recomended globaly (like availiability of engine oils, it is really hard to get a 0W-20 or 5W-20 in Greece and it may cost you more than 10€ per liter).

Also the "oil pressure" is often missunderstood. The pressure by itself does nothing to protect. The few extra psi are nill compared to the actual pressures from the combustion process. You care about oil pressure because it translates to flow, but with the lighter oil the flow to begin with and by definition will be greater even if the oil pressure (a byproduct of that) is lower.

 

[dgunay]

I used to live in the Mediterranean climate and seen 35-40 degrees every summer. We even see lower 30 degrees in Toronto nowadays.

In North America, most brands recommend one or two grades thinner oil due to emission standards than the rest of the world. For instance, back home I used to drive turbocharged Euro spec Civic Type-R, and now I drive an SI. Both are two different cars, but they have identical (K20) engines. 5w40 or 10w40 is recommended back there, but here it is 5w30. So even though they have same engine, same output, same rev, same bearing-piston/skirt clearances, they recommend different grades. Both grades are readily available and relatively cheap in both countries that I lived. CAFE mandates certain emissions to meet and try to squeeze every last MPG out of the engine they can, which is perfectly fine for daily driven car. However, if you track your car, that's a different story.

https://en.wikipedia.org/wiki/Corporate_Average_Fuel_Economy

The pressure, itself, is the most important thing to "protect". You must keep oil pressure at certain level. I doubt 0w20 or 5w20 is suitable for track conditions, as they are mainly for fuel economy. I agree that you want the lowest viscosity possible that will keep the engine safe, but you need to find a good balance between oil grade and pressure, so you won't have flow issues. For instance, if the engine runs extremely hot, and if you use 30 grade, it's going to be thinner than 20-grade csts (thereabout) at 130C, which would provide better oil pressure & film protection than xw20 grade itself at 130C as the cst of xw20 will be way lower at that temperature.

Please check this post, I hope this helps!

http://www.ft86club.com/forums/showthread.php?s=38c40c695918e32732aa66d138dc2d98&t=91820

 

[camrydriver111]

Very brave to use W20 for racing.

 

[Jetronic]

Why the high aluminium and copper?

The lead could be explained, the iron is normal, chromium is good, but alu and copper are through the roof...

I'd change the oil now, and then change the next oil early aswell. You'll have contamination from this oil in the next fill so don't bother with an analysis but put the money towards an early change.

I would run something like GC (A3/B4 rated oil) for track.

 

[nickolas84]

Originally Posted By: dgunay
Please check this post, I hope this helps!

http://www.ft86club.com/forums/showthread.php?s=38c40c695918e32732aa66d138dc2d98&t=91820


This post makes no sense...he had higher oil temps with the thinner oil, which should not happen under same conditions. Propably he run the engine harder or outside temp was higher when he had the 20 grade oil in. Having said that, 130C is close to the limit you want to run any engine oil.
Racing the GT86-BRZ with the stock 20 grade oil has been done in bitog and with great results. The same user even made the comparison with oil analysis with a 30 grade oil and the results were in favor of the stock 20 grade. You can find it here http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3305134/1