That is very true, because of having such a low CR, the 2v's boltons wont add as much as say a 96-01 Cobra or Mach 1. Add to the fact that the 2v is mostly bottom end and the 4v is all top end.

Gears, midpipe and LT's along with a tuner pretty much max this car as for bolton's.

To spend the amount to have LT's and cams installed and a dyno tune, you can find a supercharger kit for a similar amount of money.