there any way to do this? i know my car has plenty of power and hp to go past 100 but my computer cuts it off i have mods and they are getting reduced because of this how can i fix the computer/ what can be done?

This may do better in the Engineering/Technical forum.

What kind of car do you have?

You'll probably have to have the ECM sent off and reprogrammed.

Why do you need it to go faster than 100? Thats a lot faster than any speed limit signs ive gone by lately... What mods do you have that need the plus side of 100 to gain its potential?

Weapon R intake, short ram + cold air, Procharged, new pulley system and some more small stuff

and i race it at the local track it gets up to 100 really fast it just cuts off when i get there, its the only thing i cant figure out how to stop

This is the only place I know of that can reprogram or sells reprogramed ECU/PCM.
http://milzymotorsports.com/

Good Luck

Bro, go talk to your dealer about it. No point wasting your time here. The dealer can either reprogram the ECU for you or tell you they can't. Some cars have a separate Speed Limiter Unit, but I don't know if that's the case for you. Start looking into finding a different ECU, but be prepared to pay $200+ for a new one, $20-60 for a used one (which probably won't have the speed limiter removed).