Tune?
 

Do you need to install a tune to get all the benefits of headers, x pipe, axle back, cai?

I'd say no for the axle back, yes to the CAI, and probably yes to the headers and X pipe.

Definitely yes for the CAI.. Unless your upgrading to long tube headers ? A retune isn't required for just shorty headers, x-pipe and axle backs..

I finally got a tuner a few months ago, running the 93 tune, otherwise stock, car is 'spunky' compared to before... I do think 90% is due to more aggressive gas pedal mapping, but bottom end/midrange at WOT got a noticeable torque boost...
definitely makes the car even more fun to drive. wish I got one 9 yrs ago :)