NHRA 340 stockers with less motor than you have( and 400-500 pounds heavier) go mid 1.3xx 60 foot off( or quicker) the footbrake.
So it isn’t that.
Injected alky makes a lot of extra torque too
Most of us use a 2 step to launch with. In my experience if i get the launch rpm to low the car does not 60ft good and my reaction time is not good, but my car has no torque with a 273.