Well there are a couple of possibilities, a Davis Technology traction control or more likely a slew rate rev control from MSD. Jok Nicholson wrote an article about it in Drag racing on line a couple of months ago.
Basically it controls the rev limit every .001 all the way down the Track and resultantly the car can run the same (slower) ET regardless of track conditions or changes in atmospheric conditions.
( which is current legal at most bracket races)
Not to defend this guy but I think TS and TD should be allowed to run traction control for. Safety reasons.