Right now my 95 gsr runs 15.1 w/ only intake. If i install a exhaust and header, can i get into the high 14's? Or it's a waste of time.

 

You would have better luck just trying to get a better launch/60 foot time or wait until it gets cool outside to hit high 14's. After installing the header and exhaust, you could still easily stay in the 15's depending on external circumstances and your driving.