maybe a stupid question but what will this pumpkin do and is it worth it, and will it fit in a 5at?and 6mt?

 

The shorter gears increases the torque multiplication, which let's you accelerate faster so you're in powerband quicker. One of the best mods IMO. It'll work for both 5AT and 6MT, and is a direct swap if the pumpkin is off of a g35 or 350z. If its from a g37 or 370z, you might need to modify the flange and shaft, depending on which year/model it is.