It is not required but I would recommend it. There are a few on these boards still with stock diffs, and as long as you take care of it, it will hold up fine. But to really enjoy the new power I would get one.
Having said that, wheelhp is the real danger and that can happen any time a slow speeds. A little too much power in a corner, spinning in the wet, etc. I blew my stock diff with wheelhop while running a 50 shot of nitrous. The blower adds 100+ so you decide
It is great peice of mind.
I like to bang gears and take my car to the track, so in my case it is required
Nothing else is needed that is not included in the kit.
