Are all the bolt on parts really worth it?
 

I just bought another Mustang and have decided to just lightly modify the motor. It is a 1988 GT and it already has longtube headers, 3.73's, and a mild cam. All I planned to do is port and strenthen the stock heads and put all the bolt ons like TB, MAS, Underdrives and the such. Do yall think that the bolt ons will really make that much of a difference? Also what kind of gains will I get out of the head porting?

I wouldnt bother with a TB unless you change intakes to Performer or TFS street. I ported my heads and did notice slight difference at the track but unless youre doing yourself save your money for different heads like AFR, TFS or performers. It sounds like youve got most of the good stuff already
Bill

I didn't see anything about your intake - if it's the stock lower intake, porting the heads won't gain you much. For more info on how the stock lower restricts the power, paste the link in my signature. I port lowers for $100 labor + shipping typically ~$130 total.

On my brothers beater stang, It has a GT-40 Intake, Ported E7's. One equal and one unequal length header, A old H-Pipe and old 2 chamber flowmasters. Thats it. It goes 13.90s@101. Just to give you a idea.