Doug, we've been friends for 3 or 4 yrs, and i'll be the first one too tell you i don't know what's wrong with your car, but there's definately more on the table on the 60' times. Below i've posted a couple runs with a car that i built the motor in and the other car is a friend. It's a Luv truck with a 434" on 200 shot of nitrous the Biscyne has a 468" pump gas street motor and if you look at the right hand count down the Biscyne is the #3 car it has less than 1.39 60' times it weighs 3700lbs without the 200lb driver,the Luv truck has has 1.27 60' times it weighs 2550lbs.It's a true 10.5 tire truck.
My thinking is that your car is not hitting the tires hard enough, but i don't know if that converter or launch RPM I'm not smart enough too make that call, but i'm sure some of the chassis experts have the answer
The left ticket is motor only on the Biscayne
Zip.