Assuming everything is optimized...
8.0 with 300 shot.
7.70's with 500 shot.
My WAG.
It's slower NA than it used to be by a couple tenths. Mine is too, although I'm way slower than you. Used to run 11.20's pretty easily but now 11.30's - .40's. I attribute it to the colder plugs, plate restricting flow and maybe the thicker VR1 20w50 I started using in conjunction with nitrous. Maybe the weight of the added hardware for nitrous as well? Freaked me out at first thinking it was having issues but the more I thought about why...  Mine lost it all in the 60' due to the converter being 1,000 rpm tighter and 3.54 gear versus the 4.10 I used to run. My best NA pass ever (back in 2007) was 9.54 at 140.4 mph w/ a 1.32 sixty foot. Now (w/ the nitrous setup) it has run 9.69 at 142.5 mph w/ a 1.43 sixty foot. It pulls hard up top w/ this setup, it just won't leave! For this pass I was on pump gas and had the hotter -8 plugs in it...just like I always ran for NA passes. When on the nitrous I use a -10 plug and Renegade Pro 120 nitrous fuel. It also has a bigger intake manifold on it now which hurts the lowend.
CHIP
'70 hemicuda, 575" Hemi, 727, Dana 60
'69 road runner, 440-6, 18 spline 4 speed, Dana 60
'71 Demon, 340, low gear 904, 8.75
'73 Chrysler New Yorker, 440, 727, 8.75
'90 Chevy 454SS Silverado, 476" BBC, TH400, 14 bolt
'06 GMC 2500HD LBZ Duramax
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