LSJ Built Engine tune...neg idle timing and rough starts

[Japeatr]

hey all, got the car running with my zzp engine and having some issues with neg idle timing and wierd startups

05 LSJ
Mods:
ZZP Girdled block, 9.5:1 forged pistons, pauter rods, ported head, 82# valvesprings, E85, 80lb/hr injectors, return style fuel system set at 44psi (with vac hose removed), Deatchwerks DW300 Feul pump, TVS with 2.6", header and all catless exhaust, injen intake, cooling mods.

Startup issue: car will crank and start fine but hunts for idle terribly until warm, ETC % goes bananas without touching the pedal. wants to die

Running issues: neg idle timing when in closed loop.

Fueling has not been addressed yet. car has only been started about 10 times, and driven around the block 4 times. The last time around the block prior to this log it wouldnt idle for sh*t and i put a new set of plugs in it. seems to do slightly better.

trying to get it to start and idle correctly before i put it on the dyno.

attached is log showing startup issue and a long drive around the neighborhood, config file (my MAF LTFT+STFT histo isnt working if anyone can advise on that matter), and tune.

ZZP gave me a base file and it works about as well as my other tune i had worked up. the changes i made for the RSFS and some minor other things from my other tune are imported as well.

please give me advice or if anyone wants to take a crack at it i willl try it out.

[Japeatr]

bump for some views...

[fast98]

I'll look at it tonight or tomorrow and email you Vaughn.

[383_Stroker]

I'm not able to view the logs at the moment, but if your idle fueling is way off, it will hunt around at idle (since you said you hadn't tuned fuel yet).

[laser_racer]

For the negative timing problem at idle try setting the etc scaler to 4000 and see if that helps out some. Also are you having to hold the throttle to keep it running? Try the timing tables in this tune except the high octane spark.

[Japeatr]

josh/383/kendall... appreaciate the help.

ill try some of the suggestions and report back.

to answer a few questions. it will idle without additonal throttle when in netral in the drivewway but rolling up to stop signs will require a throttle blip to keep running.

kendall, havent loooked at your tune yet, but are you suggesting to look at your low octane tables for reference? is your low octane table supposed to be reference for my high octane table?

the throttle scaler i havent changed yet. ill try and let you know

*big shout out to OTTP for a late night phone call while i was at the bar watching the rangers lose to let me know Josh was looking at my tune!*

[laser_racer]

Actually that tune is from a turbo ion that's why I didn't want you to use that. The car actually has same built engine setup I might have his 80 tune some where.

[Japeatr]

Wanted to report back. Josh from OTTP and i have had a bunch of back and forths on the tune via email. Looks like the neg idle timing is by and large gone. Fueling needs help as LTFT are -14.x%.

Car is driving well with just a few idle blip of the throttle to work out.
Car will start after 2-3 cranks of prime and hold the throttle open a bit until warm.

Going to schedule A dyno to get the Maf dialed in and then address the minir drivability and startability aspects

At this point, it lloks like it is headed in the right direction at least.

Have hit low boost a few times with no concern,
Feels strong!

[HNRClothing]

Why wouldnt you dial the trims in driving around town? Get them more accurate so the dyno doesnt take longer? What did you change to help the negative idle?

[Area47]

what was the issue on this one? seems to vary a bit car to car these days

[Japeatr]

i started from the stock tune and went table by table
not sure

[Speedytec]

Was just curious to these logs, but was your "running like shit run" even in closed loop? Did not look like it, compared to the other run log of 10/02. No O2 switching...