Superformance Modifications

[Thieleng]

I am working on suspension modifications to SPF2378. Changed out the rubber bushings, put on QA-1's, changed out the spring rates on the coil overs, bought 17" wheels (ugh). The front springs are 10", changing to the 17" wheels keeps the front end too high with the lower profile Kumho's, switching to 7" coil overs 350#/300#. The wheels and tires I will use only for track and autoX. Any experience out there with regard to other suspension upgrades and/or spring rates that help with regard to handling modifications? I ordered the "402" headers and changed out the mufflers to the flow through style as suggested in the forum area. The original headers seemed restrictive as the exhaust port diameter on the Roush 427IR was larger than the supplied exhaust manifolds. Also I am thinking about doing a quick release on the steering wheel so that I can change back and forth from the standard wood to leather wrapped steering wheel. Do you know of anyone that has done this? Any other suggestions for performance/handling mods?