"So shift kit with Final Drive gears is the best combination of mods to do next? How effective are these mods and about how much time would it take off my quartermile time?"
I haven't been to the track yet. I'm not sure when I'll be going either, so I can't tell you.
The effect isn't night and day, but I think is pretty damn effective. All I can say is if your ATX, then your are missing out if you don't have these.
