Is the R worth the extra cost or is the performance difference due primarily to the tire advantage? I'd like to hear your thoughts on the matter. Russ gives his point of view in this video, enjoy and please subscribe to our channel. Thank you

https://youtu.be/HzBq_oPcEkU

Yes that C&D article totally missed the boat on the difference in overall gearing with the shorter R tires. I asked one of the Ford engineers, one who later gave me a ride in an R at LS and helped tune the suspension, about that difference and he said the change in overall gearing and improved grip accounted for the difference in 0-60 times.

There's no doubt that lighter wheels with lighter tires that are stickier account for the biggest difference in performance between an R and non-R. How much? My guess is 85-90%. Aero, weight and suspension tweaking should be the remainder of the difference.

Many of us have first hand experience of installing lighter wheels and tires on our cars and tracking them. We know there's a big difference in a cars performance from just making those changes.

To me the R represents an exceptional value and for the difference in MSRP choosing an R is a no brainer. If I could have found an R for $10K or less over sticker there would be one in my garage. For less than that difference I believe I've captured most of the performance difference by adding lighter wheels along with the SC2's and replica aero pieces. At this time I'm not feeling much need to change the suspension but I've said that before and still made changes.

BTW the R's in the photo below sit lower than the production cars. Ford must have made a change to the springs before going to production. The engineer I rode with scraped the R splitter every lap going through the corkscrew.

Same car, same set up. Loose the rear seat, add the CF wheels and the tires, add a wing and there is not that much difference between the springs. How do I know? Well.....I dug a lil deeper at a GT350 track tour. Thank DP for the info.