The README has information about my setup and what you should change to get your car running. Here is a quick summary:
99 Miata
stock engine internals and cams
Borla Induction 45mm throttles w/ 35mm air horns
ISR Header, stock midpipe w/ catalyst and unknown brand muffler
MS3ProPNP from DIYAutotune, Firmware 1.5.1 using engine state settings
AlphaN Fuel algorithm
Speed-Density Ignition algorithm
Home elevation is 7250ft ASL, ~79.5 kpa and I use realtime barometric corrections
Cold starts are good, but driving the car under 140F CLT requires three feet and it stumbles (runs rich) at idle
My tune is not perfect, but I'm able to drive the car up and down elevation, to and from the track with no issues. EGO correction does stay busy. The ignition table is mostly what I got from DIYAutotune and should be safe.
If you see a glaring mistake in my msq I would appreciate an explanation of what's wrong, how to fix it and why. I'm here to learn.
I’ve recently converted the car to ITB mode instead of AlphaN. I’m still street tuning the new VE table but I’ll post what I have when I get home today. Using this new fuel mode I should be able to use a idle air control valve when I get around to installing one. As it is, cold idle is horrible, but cold cruise is good. The car runs great once up to temperature.
I wanted to follow up on the post above. I was adviced to use the idle screw to increase air at idle, and reduce timing to get the idle speed I wanted. This method has been working great. Now the car doesn’t die returning to idle, and the timing control does a better job increasing RPMs when the fans come on. The tune in my Google drive shows the configurations, but for an idea, about 9-11 ign timing holds my idle at 950RPM when up to temperature. Cold it seems to drop to 750 no matter how much I play with timing so I give it more throttle until it gets up to temperature. Ignition timing is my only idle control mechanism. I think I’ll keep it that way with how it is working now.
After tuning the ITB mode VE table on two track days the car drives better than ever, but I noticed that it wants a lot less fuel when changing elevation so I zeroed out the table I had. Unfortunately we had some bad winter storms and I haven’t been driving it outside of town. I haven’t thought of a good method to compare a group of cells and find what difference the Baro change made so I would appreciate guidance and words of wisdom on this. At a glance, it almost seems it doesn’t need any, or very little with my current setup, but that’s just guessing by the EGO correction being almost the opposite of my Baro correction.
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