....and I've run 11.31 @ 115 with a 360, unported set of 1.88" valves, .474" lift cam weighing 3,540+ lbs. Other, similar lighter combos have been in the 10's with TTI's 1 5/8"-1 3/4" step headers.
Easiest headers I ever installed and some issues can be attributed to problems with the vehicle itself after 30-40 years of use!