Not Necessarily, Im running T-6's on my 98 w +4 timing, cool head 22cc domes, k&n w no air lid about to install some vf 3's iv had no problems with the T-6's so far....after i port i might change other than that
But cheap easy mods would be advancing your timing...theres a DIY sticky posted on here, or order one for around45-50 bucks
vf 2/3's, cool head w smaller domes like he said the list never ends......Good luck w it tho