[WardL]

It is fine to upgrade the suspension, but you think the suspension is the limiting factor in the SPF performance? How many hours do you have racing? Start out with a stock SPF suspension and you will be fine. The exhaust is perfect on my 427/520 HP engine. It is loud, but mostly from wind noise, not engine noise unless you are on it. When you are on it for the few seconds it takes to reach 100 MPH, ear plugs are the farthest thing from your thoughts..... If you set the ride height, you will be really close to a properly balanced suspension. At least that is my experience. Ride height set to specs, corner balance scales said it was perfectly balanced. I have 17" rims with 275/45 in the front and 335/35 in the back. The front wheels just touch the frame when all the way turned. I only know because I can see the tire marks on the frame. I never noticed it driving. When I put on my Hoosier autocross slicks of the same size, my left rear tire scrapes the forward, inboard wheel well fiberglass. I know some dealers cut out that section and reverse it to avoid the rub. When you buy a SPF you don't have to do anything but enjoy driving it. Of course, it is plenty fun just to look at it too... Good luck!