Removing tires frm the equation, what would be the best/most economical rear suspension mods for a '08 GT500 with 600-700hp at the crank? Car is not a daily driver and will rarely if ever see the track.
well the first thing i did was bmr adj. upper control arm. removed 99% of my wheel hop on street tires. havent got to try it with DR or slicks. that was the most important thing to me was get rid of wheel hop.
I'm not a GT500 owner but I'd probably would say get a Torque Arm and lower control arms, and maybe replace the actual Bar of the panhard to a MM one or something similiar..
J&M makes a nice rear lower control arm set as well as a nice upper rear control arm. I purchased a reinforced mount for the upper control arm as well. Add a panhard rod and you will be just fine.
I agree what everyone else has said. J&M makes a top notch upper control arm, and while you're up there go ahead and change the mount out too. Then get some lower control arms and maybe some springs. An adjustable panhard bar is a must, especially if you lower it. I also got Tokico adjustable shock/struts and really like the different settings. You can dial it to a stock like feel or really firm them up for track days.
I am in the hp range of 625+ at the rear wheels , and I went with the J&M adjustible upper control arm and the J&M billett lower control arms as well as an adjustible panhard bar and Ford Racing lowering springs.
I also added an Evolution Torque Box Brace that connects the outer and inner frame rails to the lower control arm connection.