I don't think its a DR problem, i ran DRs on my 6sp. camaro & left on the bottle & hooked like crazy, you just need to tune alittle different with stick cars, he's not hitting hard at all with 2.0 60fts. for DRs not to handle, off the bottle i went 2.0s consistantly leaving at 5000, it is very possible he just isn't getting the tires hot enough, or it could be cold weather, bad track prep, there is alot of other things that could be the problem, it also sounds like from his post he only made "1" run, it is true you can run pick up with Bias tires on stick cars, but thats useally on cars leaving alot harder then his, i think once thinks fall in place & he makes more passes, he should hook great with DRs.