My modded drag car is my Mitsubishi GTO Twin Turbo with all the latest black-market parts: stage 4 turbo, racing flywheel, triple-plate clutch, stage 5 weight reduction...
Of course, I never use it unless I'm with friends who also have their Stage 5 cars because I'm not an idiot and I already have a LMQ if I want a fast 4WD drag car, but I've gotten 9.020 out of it and could probably get sub-9 times if I spent a little more time on it.
In terms of legitimate cars, I love the Jaguar XJ12 race car. It's not the fastest drag car in the world even when tuned well, and even then I'm terrible at tuning cars, but it looks and sounds and feels fantastic (and also one can look down from your 20 mil car upon the disgusting working class drag racers in their jalopy rust buckets)