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Late Model-Corral, ’79-’13 Questions - September 2013
Sticky Tire Trouble
I finally took the big step and checked one off the bucket list by trading my '09 GT/CS for a '12 Shelby GT 500. I see lots of stuff for Mustangs advertised, but not much for GT 500s. I would like your recommendations for rear wheels and drag radials or slicks? I see lots of replacement wheels, but they're not suitable for drag radials, which don't seem to be available in the size of P285/35R19. I would like to stay under 10-inches wide if possible. I currently have 19x9.5-inch wheels, and am open to any wheel and tire combo that will mount over the 12-inch rotors and caliper in the rear.
Carvel, Alberta, Canada
There are plenty of S197 Mustang owners running drag radials these days, so you're certain to find a combination that works for you. Some owners buy a second pair of stock wheels and run drag radials at the track only (keeping the stock wheel look gives the car a sleeper mentality) and some even run drag radials year round. Of course, we do have to consider your location and must warn you that drag radials are even worse than the OE summer performance tires on the Shelby when it comes to cold temperatures (that is, below 40-degrees F). So running drag radials year round is not something we'd recommend in your situation/location. Finding 19-inch drag radials is your real problem. You'll have to either go down to an 18-inch wheel and tire or up to a 20-inch wheel and tire to fit the more popular drag radial sizes. We've not heard of any wheel manufacturer stating their wheels are not suitable for drag radial use and frankly there are thousands of late-model Mustangs on the road today with popular OE-look wheels (Cobra, Shelby, Bullitt, etc.) in aftermarket widths running drag radials. Look for a P285/40R18 drag radial, as this equates to the same overall diameter of your current rear tires and works with an 18x10 rim perfectly for a rear fitment application. It would be our suggestion to get the drag radials mounted on a second pair of wheels and just bolt them on before track use.
Ready to Rock
I've owned my '11 GT since May of last year. Since then, I've been saving up to purchase some improvements. I'm very happy with it, but want more gusto as soon as I put my foot into it. I visited a shop nearby and wound up with a quote much higher than expected. So I had to put off my upgrades. Now I'm back to being ready to hit “go.” I'm looking at spending over $10,000 and want to do this right the first time. The GT is, and will remain, my daily driver. I don't get on it all that frequently, but when I do, I don't want any hesitation and I want to feel it. I expect this means including parts for intake, exhaust, some additional tuning (since my car is an auto), and of course the supercharger (the local shop indicated that with the extra tuning parts and pieces, they could adapt the supercharger to the auto transmission). I fully expect that there should be follow-up additions to balance out the additional horsepower, like a better set of performance-oriented brakes, some exhaust work, and more, but I'm not up on all the right moves. Who can I talk to for an impartial discussion on what I should do first to avoid cutting the lifetime of my wonderful ride in half?
Via the Internet
There's nothing better for your performance dollar than bolting a supercharger to the modern modular engine found in the '05 and up Mustangs. While the 4.6L Three-Valve in the '05-'10 is long sorted out by the supercharger companies, the '11-'14 5.0L Coyote is still seeing improvements and changes to some manufacturer's kits. Each model year, as Ford makes minor changes, these companies have to go back to the drawing board and make changes to their kits as well.
Since you're rolling in a '11 GT, you've got time as your friend because the '11 GT blower kits are long since “in the can” with hardware and tuning software optimized.
We're a little worried about your choice of shop, since they stated they could “adapt” a blower kit to work with your automatic. All of the major supercharger brands (Roush, Paxton, Vortech, Kenne Bell, ProCharger, and Edelbrock) offer their supercharger kits for the '11 Mustang GT with the six-speed automatic. Strangely, the only one that does not offer an automatic trans compliant kit is Ford Racing. We were told this was a calibration factor only and custom tuning using their tuner-based blower kit would allow the FRPP blower to be installed safely.
Compliment your supercharger with exhaust upgrades, throttle body and inlet improvements, and some dyno tuning and you'll have a fun daily driver. You didn't state where you're from so we can't recommend any shops, but we do suggest seeking out your local Mustang club or visit your nearest drag strip and talk to '11 and up Mustang owners to get an idea of where to take your car locally. Shop around and find a place you're comfortable with and has a solid reputation with Coyote-powered Mustangs and you'll be fine.
Let us hear from you. Send your late-model Mustang questions or comments to: Late-Model Corral, c/o Mustang Monthly, 9036 Brittany Way, Tampa, FL 33619, or email us at email@example.com.