Supercharged 4.8 221/225 .612 or something like that. 5 speed manual. Tuned in speed density. Anyway..... Coming to a stop, the idle drops way low to 500 or less for a second or two then jumps back up to about 1100 then will level out.. Every time I come to a stop it does this.. If I'm rolling along with the clutch pedal pressed, it starts surging from 500 to 1100 then back down to about 300 then back up to 1000 then back down til I stop then it will level out. A lot of times it will dang near die or actually die if I'm making tight maneuvers and add power steering load when the idle is dropping. Also seems a little slow to respond off idle.. And acts like it has a slight stumble if you try to rev it. And adding load to it at idle it acts ilke it just wants to fall on its face. I know the cam can loose a little on the low end, but I know it didn't do any of this stock. Stock it would pull itself at idle in second just letting clutch out slow. This is getting highly annoying.. It doesn't do it quite as bad off a fresh battery disconnect, so it wasn't as pronounced when i had it tuned. All the tuner did was up the rolling idle air or something another. Didn't help a bit.
Also, i have some weird fuel trims goin on. Just reading live data from my old predator. At idle, one bank is -8 to -10 and the other bank is about -2. On decel from above 2500 rpms, it jumps to -12 on one bank and -5 on the other. Once it gets to around 2k rpms itll close the gap to around 0 and -2 or so. But it seems to maintain an offset between banks of around 5% at all times. These are long terms by the way. They never seem to stay much around 0 on either bank. go from -12 to +12. Light acceleration around +6 to 8. Decel is all negative.
I also have a terrible Backfire when i let off to shift gears at medium to high throttle input. If i accelerate fairly hard up to around 3500 and the release throttle to shift, it back fires. Highly annoying. Any ideas are greatly appreciated. Maybe a good tuner near Fort Smith, Arkansas if you know of one..

 

Maybe i just need to get a lap top and hp tuners and try to learn some stuff

 

I cant speak from experience on an super/turbo setup, but even with a small cam im my ls6 (and after paying for a dyno tune), I had to tweak the "RAF" or the Base Running Air Flow at idle. Both in Gear and Park/Nuetral. I bumped it up until it felt like i had cruise control on (auto) when I was off the gas pedal, then I had to dial it back down until it would idle well without stalling. Then I learned what a histogram was, and did it the right way with some data logging. Idle's perfect now.

Onto the other issue you have with adding steering or AC load. There's another area called AC Bump Torque Idle Spark. Shutting that off helped me.

Have your injectors been accounted for in the tune?

It's not easy to find a great tuner, especially one who isn't slammed with business and takes the time needed to get it right. I figured the changes in modifications will never end, so might as well save up and buy the damn HP Tuners Pro, and figure it out myself.

Good luck.

 

Yes. You need idle tuning performed. There are a couple of ways to do this but I use the RussK method. It never fails and works like a champ.

 

Is Polk Performance in Little Rock (Bryant) still in business?

 

Your airflow tables are all messed up. It needs a good tune.

 

It seems to run pretty good everywhere else. Cruising around and full throttle. Did 503 on a dyno with smooth power and a/f. But that dang back fire, and the idle issue is annoying. It idles fine just sitting, but when I decelerate to a stop, idle drops low.. then cracks back up and levels out., and if I'm rolling in nuetral it starts surging. its weird. Tuner originally said he had a hard time getting it to idle. And he didn't really know what to do about the backfire. Its as if something is shutting off too abruptly when I let off the throttle to shift gears. Whether that is fuel or air I don't know. and with the idle its as if something closes too much, then realizes it and over compensates, then closes again, and back and forth. Its not really a load problem. It doesn't do it just from the ac or power steering, it has to be in the down cycle of the rpms I guess you could say.. Just sitting idleing its fine.. I can do whatever I want, no affect.. But decelerating to a stop, or decelerating then turning into a driveway as the rpms are dropping to 500, makes it try to die.

 

Yep, your airflow is messed up as stated.

 

It sucks driving 3 hours just to have it not get fixed

 

Yea well welcome to Arkansas I guess. You could take a trip to Texas. Plenty of tuners in the Houston or Dallas area. Rent a car when you get there and drop yours off. Go see some stuff and pick it up in a couple of days. Not too far of a drive either.

I found this thread on LS1Tech for a guy in Tulsa.
Need a good tuner.. Tulsa, OKC, KC, ect - LS1TECH
You could try him.