94 PNP FMII Tuning Questions
 

First specs on car:

1994 Miata, GT2550R FMII kit w/FMIC, 3" DP Back, 550cc Low-Z Injectors w/resistors, MSPNP, GMIAT, LC1, Stock ignition. IIRC MS is even running 029y4 not that it matters. Stock cooling system with 160 thermostat.

Installed the kit over weekend and finally drove the car lastnight. Its running the 2550's stock wastegate pressure which best I can tell is 10psi. After several logging sessions, I think the last time max cell change came back 4 so its getting pretty close to a suitable tune.. However, I do have TWO issues...

First Megatune reports 215* CLT. All. The. Time. I've tried some searches and can't really come up with a solid answer but I do recall somewhere being told the highest temp megasquirt will read is 215 degrees. If we're on the highway it goes up on the idiot dash gauge, turn the heater on full blast and it goes back down to what megatune reports at 206 degrees. Ambient temp tonight was 69 degrees and about 90% humidity.. yet highway Cruise it stayed pegged at 215. Since this IS the stock radiator I'm assuming its likely not capable of handling the extra heat pumped into the cooling system by the turbos water jacket? We have a godspeed radiator to install, only we're missing brackets for it... Tried burping the cooling system best as possible too, didn't seem to help. Park the car after a cruise and it sits there gurgling water for fifteen minutes..

Second problem is a tuning issue. With what we've done so far the car holds a pretty solid ~11.3:1 AFR under full load, only when it gets up in the higher rpms especially in 3rd and 4th gear the engine cuts out and 'pops' a bit. While thats happening it looks like the AFR is dropping to ~12.2:1 or so. First real turbo car I've tuned completely myself so I'm learning a lot here. This is detonation, Correct? One or two times it cut out the driver observed our high tech factory installed detonation gauge was wiggling a little bit...

I'm wondering if we're putting too much timing into it? I tired DIY's stock PNP timing map but it really sucked. Like full throttle around a corner in second gear ~ 2000rpm it bogged really bad and hardly pulled to accelerate. Loaded the map we've been using for a long time and it pulls like a striped ass ape. Were sitting on an a ramp to the highway and found some dude pulling up next to us in an SRT6 crossfire who gunned it off the light. We pretty quickly ran him down and put about 4 car lengths on him before 60mph.. Those things aren't quick, but they're not turds...

We have water injection system installed but its not in use. Currently no place to put the injector yet. Thats on our list of things to do.


http://jugrnot.com/andy-cutout.jpg
http://jugrnot.com/ve-table.jpg
http://jugrnot.com/spark-table.jpg
http://jugrnot.com/afr-target.jpg

Looks.. untuned. Jk, sounds like its coming along nicely. Tach signal looks a little noisy, but still tuneable. Richen it up a little on the top end, sounds like 12.2 might be a little lean for you. Mine likes around 12.2 at the leanest, but I tune for 11.8.

The popping issue could be spark blowout. What plug wires do you have and how old are they? I could never get above 9psi with stock coils on my 94. As soon as i switched to cops I could do 15psi fine.

I was asking about his plugs lastnight and he bought some different temps to try. IIRC he has the 10mm magnacore huge ass plug wires and they're about a year old. Sadly after the troubles he's seen me go through with COPs I doubt he'll ever consider that switch. :(

Got the radiator mounted today so hopefully that'll help things a bit.

Those spark #'s are really aggressive. I recommend you put a timing light on the car and check the tune with det cans. That's almost as aggressive as mine...which will change again this thursday.

Have him switch to ngk blues. Finishline performance has them for cheap. My magnacore plug wires were horrible.

Good news. Got that GodSpeed radiator installed and helped with coolant temps quite a lot. Swapped out for a little hotter plug and gaped them at .033 and solved the popping problem. Car pulls like a striped ass ape.. On wastegate pressure we've seen 13psi near redline. :D

Going to the dyno friday, hoping for good numbers.

im doing a fm turbo with the mspnp. what did you do to the egr? this got me confused.

The AFR targets for VE table 1 you have pictured at the bottom is completely retarded. I hope you're not running closed loop to 21 psi. :gay:

If you're using it for tuning, then it's still wrong. You want to use the 12x12 table in MLV.

You should also try TunerStudio instead of MegaTune. TS is the shit.

You don't do anything with it. Take it off and put on a block off plate if you want. Or just do nothing.

Alright. Now I'm interested in removing the whole system.