To excede 120 in that little shitbox ricer is stoopid without putting more money into the car than its worth. Start with a 6 point cage, 5 point harnesses, and Z rated tires. Then you can re-design and build a whole new brake system.... 102mph isn't worth a damn if you can't get it stopped. Now, once you have those little projects out of the way, you need to add some downforce so you don't float off the road into the iceplant at speed.
A firesuit and brain bucket is a real good idea too. Next you gotta figure out what track your going to run that little POS at, because in *MOST* states, if you get caught running 20mph over the limit, they haul your ass off to jail for reckless driving, exhibition of speed, and racing on public streets, then don't count on getting your license back for a number of years.
Now to the drive train.... to keep the engine from having a catistrophic failure, you will need to do around $30,000 of work to the engine an tranny, the least of which is the chip, and laptop to tweak it once you get it on the dyno.
If you got more dollars than sense, then go ahead on with it.... but in stock trim, that 120mph SAFETY SHUTDOWN is there for a reason.
If you insist on trying this stunt, than the brain bucket needs to be really, really small, because you don't have a brain to put in it.

And yes, I used to build and race cars.