Ok here is a quick look at what a good base build for a 04 GT.
Manufactures
STEEDA
RPM Outlet
Parts List
STEEDA
Springs
Steeda V8 Competition Springs $269.96
DISC.
• Lowers the car approximately 11/4â€
• Ultimate handling with a street-able ride
• Slightly firmer ride than Sport Springs
Steeda Polyurethane Front Isolators - '79-'04 $29.95
Steeda Polyurethane Rear Isolators - '79-'04 $29.95
DISC.
Spring isolator bushings isolate the car from road vibrations. Missing or worn out isolators can make the car sag or sit unevenly. Replace them with durable urethane isolators.
Struts
Tokico Front Struts $139.95 each
Tokico Rear Struts $68.95 each
DISC.
Tokico's high performance struts and shocks feature the same high quality as their top-of-the-line Illumina shocks in a less expensive non-adjustable package. Their dampening is tuned to a firm "sport" mode for maximum control without being harsh.
Chassis
Steeda Front Strut $149.95
RPM Outlet
Chassis
Kenny Brown Rear Strut $139.95
Kenny Brown Extreme Braces $199.95
Kenny Brown Jacking Rails $89.95
Ok... This is a total chassis build and a medium suspension build but overall will have an amazing affect on the car and its capabilities. The total for this project is roughly $1,120.00 (without tax or shipping). If you have the cash for it this setup will last you a long ways until your power levels bring you cornering speeds up to where you need to upgrade to Coil-Overs. But personally you don’t need all this now. To fit into the less expensive side of things here is the setup I recommend to start with.
Steeda V8 Competition Springs $269.96
Steeda Polyurethane Front Isolators - '79-'04 $29.95
Steeda Polyurethane Rear Isolators - '79-'04 $29.95
Steeda Front Strut $149.95
Kenny Brown Rear Strut $139.95
Total est $620
(You don’t necessarily need the isolators which will save you $60 ($560) but they will help with the ride quality and a slight increase in response)
The struts are not need as much as the lower ride height. The springs will make a good amount of stiffness and the lower height will make its slide smoother. I do suggest urethane bushings for the swaybars, tie-rod ends, and struts. (Which are cheap, like anywhere from $9 to $25) This will make you stock struts feel better than new. You can knock off another $140 ($480 or $420 with no isolators) by getting rid of the rear strut but it really does help. I have the steeda front and all of the Kenny Brown parts I have listed and my convt is like riding in a caged coupe. As far as the front strut goes you need it… The front of the car is like a shoebox… You put pressure on it and it just twists and bends so it’s a must. Hope that this is a help and let me know if you need more specifics.