M1 0W-40 3 Track days Mx5 / Miata (Extend Drain?)

[Ned_Loh]

Originally Posted By: Gasbuggy


The OEM tunes are usually too rich at wide open throttle. He should check out a miata forum to find out more.


You are correct. I have my own wide band and have checked tune. With intake/headers/exhaust, runs about 12:1 at full noise.

Spec miata racers use a fuel pressure regulator to lean out for best power/torque

 

[Ned_Loh]

Originally Posted By: Ned_Loh

pondering this a bit more and reading this site. If the high silicon was from dirt or coolant ingestion wouldn't some of the other markers be higher? Cylinder head was replaced just before the first UOA, so I wonder if the Si is still leaching out from some of the sealers or gaskets used. I guess all I can do is change a little earlier (say 4 or 5 track days) next time and see. If the number trends down I may be able to increase the OCI back to 6 track days.

With regard to the fuel dilaution at 4%. Whilst not great it is possibly not an issues as nothing is showing signs that the film strength has broken down?


THANKS TO YOU ALL FOR YOUR INPUT SO FAR. I will change after 4-5 track days and post up results.

At the risk of quoting myself I would be very interested to hear from anyone on the above questions...which are in summary:

- If the silicone was from dirt shouldn't some other markers be higher?
- Fuel dilution is high, but nothing in the analysis is ahowing film strength has broken down?

 

[OVERKILL]

Fuel dilution is completely normal, you should have seen what my M5 was doing. Factory rich tunes. I expect when the UOA comes back from my SRT-8, it will show the same thing. It gives itself black tailpipes just like the M5 did, which is an indication of an overly rich factory (performance) tune. Your UOA looks excellent, the product held up extremely well and I would continue doing what you are doing.

Regarding your question on silicon, yes, a sealer, if exposed to the oil, will elevate that number, and since you've been into the motor, this is quite likely the source.