The BFG's would do the wobble deal @ high speeds when they where Bad as in belt separation. Now M/T doesn't recommended screwing them cause of the steel belt construction. That's what M/T told me this summer when I tested some tires for them. I would try some more air? Are they balanced good?
I used the MT radial for the first time this year at Milan it was on a very bad day the track was in the upper 130 degree mark with alot of street car's needless to say even thinking you can hook that is a joke but we were there and needed passes on a new engine so what the hell, I have seen the wobbles in the video's before but never experienced it... untill that day and I can tell ya it is some scarry shit, at first I thought I was in trouble but I remembered that radial's do this so I stayed in it VERY unnerving the car went straight but with a slite toose from side to side, I was told that the weight of the tire had something to do with it being 40 pound's and all or it could have been the track who know's, I'm gonna try them again next year hopefully with better luck
I had the wobble real bad, a sort of "twisting" back and forth from end to end which would continue all the way down track, never deminishing till i lift at the lights.
On one particular day it got so bad i lifted on two out of four passes, afraid it would break loose and crash. On the other passes two guys that pit for a buddys supercomp door car couldn't believe i stayed in it, it was so obvious.
My car seems to have all the things wrong that will agravate this problem with a drag radial slick type tire. I have a 106 inch chassis, 3000 race wieght, somewhat high center of gravity, and a threespeed auto for providing plenty of low gear torque to get the antics going.
I use a M/T 14.5 x 33 x 15 radail drag slick, with air pressure at 11 psi. The higher the pressure, the worse the problem. Same with shock settings. The stiffer the shock, the worse the problem. The anit roll i built is also probably a contributer, and probably the worst offender of all. It allows no rollrotation whatsoever, as the main tube is made of MS 1 3/4 x .134 wall tube. To help my problem i removed the passenger side link on the anti roll, and made a slipjoint link out of it so it only holds in on direction. I also made it so it has a piece of rubber shaped like a donut between the tubes to act as a sort of cushion. All this helped, but still the car is sort of scary. The radial tires quit working at 27 passes, and the 60 fts went from 1.28 to 1.33+ just like that, so i am going back to my standard goodyear 33.6 x 15.1 x 15 tires.