[MrClean]

Yesterday, I talked to Maximum Motorsports and Performance Autosports about the suspension and steering of the PJ. Both were very good conversations.

What I learned from them:

1. The S197 chassis was designed around IRS, not for a solid rear axle setup.

2. There is concensus that the stock steering on the Mustang is designed for the masses, not the driver/track enthusiast.

3. The "rubber" on the car (not tires, but bushings) is soft to give the car cruising smoothness and pleasing NHV, but this can translate to a floaty ride and driver isolation (lack of dynamic feedback).

What does this mean?

Overall, for me, it means a high pucker factor if you drive at triple digit speeds (on track).

Individually, it means:

1. The car's suspension geometry has been compromised to accomodate the solid rear axle and resultantly has compliance and travel issues (read: traction and stability issues ---> think about how the car's balance/traction is affected when you bottom out against the bump stops). So, lowering an S197 doesn't necessarily mean improved handling, even with the lower COG.

2. What's good for boulevard cruising isn't going to install confidence on track. The power steering is overboosted and lacks feedback, especially at speed. Small inputs at speed can translate to big changes in direction and combine that with the lack of feedback and you're overly challenged to correctly navigate a high speed turn sucessfully.

3. Another feedback and traction issue is the low durometer rubber the car's suspension and steering components include. Again, what's pleasing for cruising around town, removes feedback and confidence at speed. Some might also call this lack of feedback "numbness" or "isolation" from the driving experience.

What's recommended and why?

Regarding item 1. Saleen's Speedlab makes a coilover kit especially suited for our S197 cars. Compliancy and better traction, via well chosen spring rates and adjustable shock dampening is attained, while allowing you to control the height. Again, lower does not necessarily mean better, so it's good to have control over height.

Regarding item 2. A proper alignment along with lower control arms that have higher durometer bushings will make a huge difference for most driving situations. Zero out the caster as much as possible, turn the toe in (not too much that you chew up tires) and let that camber go NEGATIVE! I was told -1.3 to -1.9 is good for street and some track/autocross, but if you really want to optimize track driving, taking camber to -3 will do wonders for handling and high speed stability (note: the Speedlab coilovers come with camber/caster plates for more adjustment capability). Finally, if this doesn't "fix" the steering speed and feedback enough for you, then the FR500 steering rack in the Ford Racing catalog will. This unit reduces the boost, improving feedback, and slows the ratio to improve higher speed driving control. At about $1000 plus install, it is the more expensive way to go.

3. As mentioned above, lower control arms with high durometer bushings will get rid of the feeling of isolation and transmit more of the car's dynamics to you, but the drawback here is more noise transmission to the cabin - gear whine for instance in the case of the rear control arms. Rear lower control arms are a good controlled way to start the modding (ehm, clearing throat, "enhancements"). I hear the front lower control arms can be squeaky if not lubed often.

So, there you have it - from the experts at these two fine Mustang focused companies; both with years and years of experience both on and off track with what works and doesn't work on our cars.

I plan to take the advice (I've heard on this forum and from MM and PA) of doing the Speedlab coilovers with camber/caster plates, along with the lower control arms and a proper alignment. If that doesn't take care of the steering for me, then I'll plan to do the FR500 steering rack.