Looking to add some oomph to your V6 car? Check out these links:

http://rpm-mustangs.com/main.html (their project car: http://rpm-mustangs.com/projectcars/83/index.html )

http://www.racerwalsh.com/v6_3.8.htm

Exhaust:
You can swap the manifolds for the nicer (and lighter weight) ones found on 94-98 V6 Mustangs. H-pipes made for 94-98 V6 Mustangs will fit on earlier cars after doing some grinding on the transmission crossmember. A "double-hump" transmission crossmember may eliminate the need to grind.

Gears:
V6 cars have the infamous-to-V8-owners 7.5" rear. As long as the modifications are mild, a V6 shouldn't have any problems with a 7.5" rear. Gear kits ARE available for the 7.5" should you want to try your hand at a gear swap for more off-the-line grunt.

Traction:
All the mods in the world won't do you a bit of good unless you can get it to the ground. If you find yourself spinning your tires constantly, get stickier tires. Drag radials may be overkill or they may have too short of a treadlife for what you want, but when planning on a tire purchase, check into the treadwear rating of the tires. There are many high performance tires with treadwear #s in the 200-300 range. The lower the number the stickier the tire. BUT, also remember, the sticker the tire, the quicker they will wear. Firestone Firehawk SZ50 EPs are a nice compromise of wet and try traction with good treadwear, for example.

Brakes/Wheels:
For EXCELLENT brake upgrade information as well as five lug conversion infromation check out this link: http://svo73mm.cjb.net