I had to read back a bit to see what you ended up with for a combo.

You are obviously experiencing some "new combo blues".
One you get it sorted out it should go(at least) 8-10mph better.
ET's are much more dependant on how well you can get the car to leave.
"Street" cars with a std trans and mild gearing don't usually 60' nearly as well as a comparable auto, but mid-low 12's should be no problem.