i have a 98 gt vert 50k and want to do best bang for $
it is totally stock has 327 posi or limited slip both tires spin easily
i was told to change to 373 gears
i was also told you could chqnge cams and intake to pi and get within 5 hp of changing to pi heads

i am a 1st time mustang owner and would like some input

 

4.10s is the way to go with modulars...
If your not familiar with these cars then i'd definately suggest doing a PI swap imediately. It will wake your car up with an additional 40-50hp and with some 4.10's and other minor boltons will give you a respectable street cruiser.