MT ET Street Drag Radial sizes

I'm currently running 275/50R15 on 9" Draglites. They hooked most of the time. I took the spare and jack out of the back and I spun. I wouldn't think that it wouldn't make that much of a difference. The spare and jack are back in.

It's time to replace the worn Mickey Thompsons. I was looking at the 275/60R15. I have a set of 10" Draglites to put them on. I know I have the power to turn the 28" tires. I see that they have a smaller tread width though. What tire would give me more traction, the 26" or the 28"??

I have done a 1.6 60' and been up to 1.8.
I have doing 3500 to 4000 rpm starts with letting the clutch up fast, not dumping. If I get it right the tire hook and I'm off and shift right into 2nd. I have the shift light set at 5200 rpm. I don't look at the tach, but the shift light may come on at or near the 1/4 mile while in 4th. I have been trapping at 119 to 121.
Don't have dyno figures to show where the power band, but it feels like it's still pulling hard when I do the 2nd to 3rd and 3rd to 4th shifts.