1998 mustang v6 vs 2001 v6

[btr711]

I have many things to ask.

I bought my 98 mustang last year for 6grand (automatic)
My friend bought a 2001 for 2 grand but his is messed up badly.
~it needs a new clutch, pressure plate, speed o doesn't work
and the dash lights dont work, and a few other things.

Both are 3.8 v6's.

1. If his mustang was not broken, how much faster would it be? Does it produce more power(if so how much)
2. Is their anything that i can do to increase my output with less than $400?
3. I have high performance tires on my car, so if we were to drag race, would it help me out just a little bit, or is the v6 too weak for the tires to even matter?