Programming out hesitation on tip-in? (big injectors)

Here's the combo:

383, 8.3/1, 224/236-114 cam, AFR 210's, T-76 GTS turbo, aftercooler.

I'm running the stock '95 ECM, LJ's impedence converter, 84 lb/hr injectors, a descreened MAF on the pressure side of the turbo, and using TunerCAT to tune it.

I have 2 problems I can't seem to program out:
1. When I abruptly give it throttle, the A/F ratio jumps to 18/1, and the engine hesitates, sometimes backfires.
2. When the motor warms up, it won't start without giving it some throttle.

Any ideas on what I should do with the programming?

Thanks,
Mike

Looks we have very simular setup exept for the turbo.
Had the same problem when i installed the low Z injectors,
In tunercat:
I raised the MAF1 table around 5-8% in the area 8-22 g/sec. Dont really understand why that worked but it did :D
Lowered the initial/crank start up A/F in the 40-1xx degrees area widh aprox 10-15% (scaled widh 0.88 for example)
Set the injector offset vs voltage flat from 10-16volt (used the 13,5volt value)
Thats how i solved the problem.

Mike, are you running a monoblade?

No, I just have a 52 mm TB.

Lisa, I can't find the "initial/crank start up A/F" in TunerCAT. What do you use to tune?

Mike

Looks we have very simular setup exept for the turbo.
Had the same problem when i installed the low Z injectors,
In tunercat:
I raised the MAF1 table around 5-8% in the area 8-22 g/sec. Dont really understand why that worked but it did :D
Lowered the initial/crank start up A/F in the 40-1xx degrees area widh aprox 10-15% (scaled widh 0.88 for example)
Set the injector offset vs voltage flat from 10-16volt (used the 13,5volt value)
Thats how i solved the problem.

:cool:

No, I just have a 52 mm TB.

Lisa, I can't find the "initial/crank start up A/F" in TunerCAT. What do you use to tune?

Mike


I think that is in the new V of TC, i am sure i have seen that table....

-J

you need a newer definiton file, The correct name on the table are
Initial startup AFR enrichment VS colant
I also decreased
1st primepulse vs coolant
2nd primepulse vs coolant
widh 40-50%

ake eliasson