05 LS2 Supercharged GTO - Backfire / Won't start

:worship: to all those who understand this stuff. I understand dynamo theory, but I'll be darned if I understand a VE table :D I've been reading and trying to learn for a month.

So here's the deal. Prior to my upgrades, this is what I had:

LS2, stock internals, stock cam
1-3/4 Kooks LT Catted
MP112 s/c running @ 7psi
42# injectors
Meth injection

And it ran fine. Well, then I did this:

1-7/8 Kooks LT Catted
Upped boost, should be doubled
63# Siemens injectors

Connected to the car, saved my original tune. Then I uploaded the new tune which my tuner said he corrected for increased boost and the injectors. We went to fire it up lastnight, and it just occasionally backfires in the intake. It's not a consistent backfire--if we hold the key to the start position for like 30 seconds, you'll hear a pop maybe every 8 or 10 seconds, so it's not a continual "pop pop pop".

After doing research, this leads me to believe something along the lines of:

Cam sensor
Too much startup fuel
Too little startup air

At least, my extremely trite and humbled lacking HPT experience with research tells me that. Maybe I'm wrong. IATs are just a degree or so above ambient, until of course it back fires. RPMs never get above about 150 when trying to start--seems kinda low to me, but maybe it's because it's that well-overdriven supercharger. We pulled some plugs, they're getting spark, and they're getting fuel. The ones we pulled didn't appear fouled.

Going to head out to the garage tonight and recheck my vacuum lines, also check my cam/crank sensor wiring and check the sparkplugs to make sure they're clean.

Can anyone help? I'm posting the original tune and the new tune to compare.

Again, I'm super new to this but I've been reading, researching and trying to figure things out. I checked the differences between the two in HPT--still learning though, so I figured I'd let you experts yell at me.

Now, the "new" tune was designed for 60# injectors supposeldy. The injectors I'm actually using are 63#. i didn't think it would make a big difference to at least get the thing started.. i figured I could then fine tune it.

Bump out of mercy

Wow, nothing guys?

Resolved: Coil pack wiring on one bank was bad. Pulled a degree of timing to smooth out the initial start. Idles well. Now on to fine tuning. Thanks for at least reading :D

I just saw it and yes I knew it was the dreaded upside down and backwards coil pigtail FTL. LOL

Yeah, I kept thinking.. there's no way in hell the cam is 180* out.. we each checked it 3 times.. it had to be something simple. So I started with the coilpacks :D

Nice build you have going btw!

Yes sir, Could I get a copy of this tune to try in my car? it is real close to yours. I'm new on here and learning. I have not got to crank it yet. I wanted to try it with this tune. i don't know if that is something you do on here or not?