get a stock maf and tune it for a stock one. Otherwise your going to be chasing your tail with issues from it forever.
The lt4s still flow up there (6.5k) but thats going to depend on how much work is done to them. Also how good the port work has a lot to do with it.
Do you have any flow numbers?
Who did the work?
The new stall will help out the times alot. But you should get the power you want out of the motor and than worry about putting it to the ground. That 109 trap goes back to what i said about bolt on cars with dyno numbers. That stands behind the 320rwhp.
You may need a taller tire for the 4.10.
good luck

 

Im not sure on the heads, I know the bowls were worked and intake runners had minor work to them.. I wouldnt put them much over stock stock flow.. So would the ported stock maf work or do I have to get once with the divider and screen in it? Also when I had it on the mobile dyno like 2 years ago it made 347rwhp@5600rpm with my dual comp cam valve springs, I put beehives on there since..

 

I was running 12.30's with that same MPH on mid 1.7 60's. Shifted at 6300 rpm's, 26" drag radials, 3000 Midwest converter.

 

Just curious but are your heads GM LT4's or AFR LT4's or perhaps something else ?