xxx-s hop ups worth it?
 

is the black belt conversion kit worth it for the xxx-s g+, because my friend cutt everything other tooth off my yellow belt already and we were wonderin if the belt is a noticeable difference on a smaller more accelertion track, we got the car hooked up really good now we just need speed we won sunday and broke the track record by 2 laps because of his motor tuning skills, now we wanna break it again next sunday wut can we do 2 make the car go faster

I would say that the black conversion is better than yellow belt..
it's also thet use different pulley too the help reduce drag in the drivetrain:)

is it noticeable and worth 20$

yes and yes.

I might be able get it cheaper for ya ..let you know later tomorrow..

should i cut every other tooth off to reduce even more friction

how cheap?

Don't cut any teeth off the black belt! It's more free than a cut yellow belt.

black belt eliminates the belt skipping/clicking, so you should have better acceleration.