Just purchased a turbo Miata with Greddy TD04-15G and a bunch of other support mods (440cc injectors, MS PNP, Intercooler, exchaust, coil-packs, etc).

The current tune is a bit troublesome in that:
- The car is knocking at high-boost high rpm (12psi). I suspect timing advance maps are off since AFRs look good (10.5:1)
- The car has intermittent idle surge issues

Would love to get some help tuning the car, anyone in Northern California that you'd recommend? (preferabley with Dyno, but not required).

- Chris

 

Jei at Blacktrax in Milpitas has tuned many NA and FI Miatas, including mine through all of its iterations. They do, of course, have a dyno to tune it.

 

Call or email Jei but give it a day or two, as he travels often in support of a shop-sponsored drift race car.

 

Jei @ Blacktrack in Milpitas, Anthony @ Hybridworks in Vallejo, Richard @ VL Motorsports in Livermore would be my personal recommendations.
Have you connected to your MS via laptop and tunerstudio yet? Would it be possible to post your tune/datalog of issues?

 

Tune file attached.

Timing Tables


AFR Tables:

AFR TablesTune is attached:

 

Well,
If that is actually your AFR table, you are in trouble. The AFR load scale only goes from 30-100. 30kpa is too low because you probably see more vacuum than that during decel, which should be on your map for good measure, even though it wont be delivering the fuel there. you should be able to see your needle float on your map at all times.
100kpa is good for a N/A, but you're at 12psi of boost which is over 200kpa i think, so your maps dont correspond to each other. I would imagine this would not make drivability very great..
Also you said 10.5:1 in full boost - thats too rich. 11.5-12:1 would suffice and make the most of your engine. but your AFR map scaling is contributing to this issue.

Reduce timing at idle to 14* or so.. 18* shouldnt be quite necessary, even if it works. Everything in your idle range on your AFR map, even it out. so instead of 13.2, 13.9, 13.7, 13.4, etc... have them ALL be 13.5 (or preferrably 14.0, or even 14.7:1), that way the idle will not hunt for alternative AFR's.
Same with fuel map... flatten out the curve at idle so it doesn't hunt for fuel PW.
BTW, is your EGO control on? should be under general settings. sorry, I'll check your actual tune on my tuning laptop later.

if it is on, turn it off (raise lower limit to rpm that is wayyy high, or just turn off) and set your idle VE, timing, and AFR with engine fully warm and all other sensors happy (ie. NOT heatsoaked...) and loads turned off (headlights off, a/c off). Evening/night is the best for this. Get your idle happy without any assistance from ego control or closed loop or whatever. Either auto tune or manual tune for a good 14.0/14.7 idle or whatever the hell you want. Then afterwards you can turn EGO back on, which will keep your idle AFR in check, that is, after you set it to be happy by itself. hope that somewhat makes sense. at least it will idle smoothly. then go auto tune with your AFR map scaled correctly, with Cell Resistance turned to Easy, and be smooth with your throttle inputs to help with auto-tuning because it's only so intelligent. Return back with new tune and datalog!

 

Where are you in northern California? The "northern" part of California spans across a few states in distance comparing them to the eastern states.