I had my 87 dodge d100 at the track last night and I now realize just how badly I need to improve traction on it. It's got a built 340 stroker and I can't even come close to getting traction until well into 2nd gear.
I'm running cheapo 255/65/15 tires so that is something I obviously need to upgrade. Any suggestions on that? I would like to keep the same rims so something in that approximated size would be preferred.
What about suspension mods? Right now it's completely stock.

Drop about 10lbs of pressure in the tires and ease into the throttle off the line. Nail it once you start moving.

I didn't drop the tire pressure but I did ease into it. No matter when I jumped on it, the tires would get loose.

maybe some P275/60R15 Drag radials 28 inches tall by 8.5-9 inch tread width summitracing.com has a selection on them

do you have any wheel hop when it breaks loose or do you have plenty of torque to spin them?

my springs are worn so I made a set of traction bars that bolt on top of spring under u-bolts and had a rubber shock bushing on a bayonet stud in a hole I drilled in the front spring hanger.

this will really help control the axle wrap on the axle truck chassis.

shackle flip with axle on top of springs and a set of cal-tracs or lift bars/traction bars.

I have home made Caltrac bars with stock leaf springs and 315/60 M/T Drag Radials on my D50 that is real nose heavy and drive to track. I have had a 1.33 best 60 ft. so far.