The cam would give you about 20 horsepower at best, and thats with with an adjustable cam gear, and you'd also have to get it dyno tuned to squeeze that much out of it.

A 35 shot of nitrous would probably put down 50+ hp to the wheels instantly working alongside the Supercharger.

Nitrous would be the way to go. You could also find a tranny thats geared longer than your EX's. The d15b7 (DX) tranny when mated to a d16z6 or d16y8 , has a 1st gear that goes over 40mph, a second that goes to over 70mph, and a 3rd gear that goes to almost 110 MPH. Im not sure what 4th will go to.

The trannies are like 100 bucks or less. And You could probably find a cheap ZEX wet nitrous kit on ThePartsTrader.com for 300 - 450$ depending on the accessories.