ive got a 04 h/c 5.3 full bolt on. put the 08 intake with 32lbs inj.90mm ls2 throttle body and the tac mod.when we fire it up, the truck fires then a little stumble and smokes black . alot of fuel?. my ? is that if the throttle opens from the bottom could it cause this issue? is this a tunning issue? i know the intake was designed for a truck and the throttle for a car. is there a difference? it runs good feels strong just smokes . please help

 

Smoke is not a good thing.Did you scale the IFR (injector flow rate) table correct?Do you have a wideband?
What software are you using?
I am not sure what you mean by this

"my ? is that if the throttle opens from the bottom could it cause this issue?"

 

Since you put bigger TB and Injectors I'd have to guess the mixture isn't right and needs tuning

 

yup its on the wideband,hp tuner,I MEAN THE truck throttle 87mm opens from the top and the ls2 90mm opens the opposite way, from the bottom.do u know what i mean now? i just dont know if u can use a ls2 90mm with a truck intake (2008)? if so then (black smoke at start up) this would be tunning related issue right?

 

that's a tuning issue, flow rates and pulse width. Are they Chevy/delphi injectors, or some other brand

the TB opening from the bottom vs the top doesn't change anything . . . espically if its ported

 

YUP THEY R flex fuel 32lbs inj.so im hoping this is a tunning issue

 

Sounds like a tuning issue. The only thing that you would change is the throttle area in the tune, but the 87mm is so close to the 90mm that it made no difference on my truck, at least from SOTP.
On a different note, I tried installing an LS2/LS7 TB on my truck a few months back and couldn't get it to open all the way to WOT. I ran a thread on here about it for weeks, but no one had a fix for it. Apparently the car TBs have a different voltage signal from the truck 87mm, or at least that's my theory. If you check yours you may find that it doesn't go full WOT. It took me a while to realize it, because like you said the throttle blade swivels in the opposite direction and the truck intake has an downward angle at the TB. I ended up porting the ridge out of my stock 87mm and it works much better than the 90mm did, IMHO.

 

YUP I HOPE Ita a tunning issue.i will be working on the start up table friday so well see thanks

 

My opinion as well.