Try shifting at 5000-5200, that's where my trucks ran best with stock cams- it was worth 2/10 and 2 mph on a stock truck, I had a custom 206* in one that liked 5800-5900.
I have been giving some thought- I might slap the bigger manifolds on and just run some short dumps. This would allow me to seperate the two issues (cam and manifolds) and figure out which is the worst offender.
I doubt the rest of the exhaust system is the issue (2.5" mandrel bent with an H-pipe) so if the car suddenly picks up a bunch of power I know which direction to go.
This would be quick and easy to do which is good as I'm suppose to be winterizing the house soon not tinkering further with cars!
Looking at the vids in slow-mo shows the car hitting the slicks but not spinning after the first run or two, it simply isn't making enough power to shorttime better.
