Hi clubt,clubt said:
What kind of track driving do you want to do? Drag strip, closed or open road course, autocross? All you should need is a 4 point roll bar to run most places with a stock car like yours and for a test and tune night maybe not even that.
As to your spring questions, IMO, sport springs much like a loud, shinney axle back exhaust for most people (with new Mustangs), are purchased for appearances and that's the truth.
For drivers that enjoy a good twisty bit of road, autocross or road course once in a while a good set of sport springs and good adjustable sport struts and dampers will be key to finding handling happiness with the sn197 pony. I know that adding a set of struts and dampers helped me get into my '05 GT's handling a LOT more. While a stock '05 Mustang GT is a better handling car than even a well modified '03-'04 GT, the improvement in handling performance is nothing short of amazing once you get the car aligned and set the strut and shock dampening right. The drivers with only a set of sport springs installed on their '05's have NO idea what they are missing in handling performance!
Buying and installing a good set of sport springs IMO is a waste of perfectly good money unless you also get a set of good quality struts and dampers to control those new, stiffer and lower sport springs. The stock Ford struts and dampers are way too soft for sport springs and the rear dampers are downright dangerous when pressed hard or in a sudden emergency maneuver.
Also be aware that if you get a good set of sport springs that lower the car more than an inch or you just want to get the best possible handling out of your sn197 you should also get at the very least an adjustable panhard bar to allow re-centering the rear axle under the car.
Also very important (if you want your chassis to last), is a heavy duty panhard bar support brace to help keep the chassis side of the panhard bar in the right place and reduce the chance of tearing out the chassis side panhard bar pick up point. A good lightweight, stiff, ADJUSTABLE (important!), panhard bar and brace can make the '05's handle much better and allows a better alignment and more consistent handling turning left vs. right.
Expect to spend about $1,300 for parts (springs, struts, dampers, adjustable panhard bar and HD panhard bar brace), and $300-$500 for installation and 4 wheel alignment. Or if you have basic metric hand tools, a floor jack and jack stands (or have a friend who does), save the money and install the whole she-bang yourself in about 4 or 5 hours.
For real drag strip use leave the springs alone and get a set of adjustable dampers that can be adjusted for strip use. Look for 50/50 and 90/10 shocks for dedicated strip use. For adjustables look at QA1, they make some of the best adjustables out there. While you are messing under the rear of the car with your suspension for the strip look into a set of adjustable upper and lower control arms with urethane bushings. They will eliminate wheel hop from the LCA's and UCA's winding up and allow you to set your pinion angle. I also think that BMR's adjustable UCA mount and weld in LCA axle side mounts will be usefull even with a near stock motor and auto with a looser converter.
These items will get you launched hard wih DOT slicks. Also if you can find them, a set of stiffer urethane bushing for the stock panhard bar or a new fixed length panhard bar with urethane bushings will go a long way to keeping your pony launching in a straight line.
Just some ideas to consider.
