how practical is it to go all motor i have a 2000 gt five speed

With a 2v 4.6L 360 crank horsepower is possible. You could be 11 seconds on the motor. But MPG obviously takes a major dump. Plus it cost money.

so is it cheeper to supercharge or go all motor im new to the 2v 4.6

S/C would be your best bet when it comes to cost/hp gain ratio.

Using motor only works best up to about 320 crank horses. After that it's expensive. Basically, your major mods are port and polish your PI heads, valve train, and better pistions. Plus exhaust and intake. Unless I win a lottery I can't afford a blower, so motor is all I got. I'll do a moderate build up, then add some nitrous.