What transmission is in it? Assume its a glide. For 140 the car should be much quicker than it is, easy 9.50's and if everything worked right 9.40's. Which makes that 60' even more horrific. A converter in a glide is a pretty critical part of the equation. I would also want to look at what shocks it has and how that ladder bar is installed. Maybe the car is just fighting itself off the line, but I would be VERY surprised if that converter was even close for the combo.