I was making 600hp NA and launching at 5500 off the transbrake at 3200lb race weight.
But these cars need a bunch of bracing and girdles at 450-550hp at 3800lb?
Im not trying to call anyone wrong or call anyone out, I just want to learn before I make a costly mistake.
A transbrake doesn't hit the drivetrain near as hard as a clutch car does. I'd say that is the biggest factor in your comparison, 2nd being the 600 lbs or so weight difference, 3rd being the narrower axle in the older cars which makes it inherently stiffer.