Modding a Mustang GT: The Final Product … Kinda

“The Perfect Purchase” was posted back on June 9th and told the story of how I searched high and low for the perfect street/track car. I talked about why I purchased a 2013 Mustang GT, and further still, what my future plans were.

On July 10th “Muscle Evolved: Modding a Mustang GT” went up, as did a video I produced for /DRIVE on why I chose to go with components from Cortex Racing. We heard from Filip, the owner of Cortex, and you got to see first-hand what actually goes into modifying an automobile the right way.

It’s now time for “Modding a Mustang GT: The Final Product… Kinda”. Here I’m going to list exactly what parts were placed on the car, in what stages we did them, cost, and what (if any) my future plans are.

Since taking possession of the Mustang back in September of 2012, I’ve had one goal – make it into the best track/street car that my budget would allow. I did my due diligence and research, talked to multiple vendors, and then in the beginning of this year, started the transformation from mild-mannered street Mustang, to one that pisses off Porsches, Corvettes and all other manner of high-end automobile.

The build was done in three stages with each one producing different results. Keep in mind as well that just because I went with Cortex Racing, it doesn’t mean you have to. Do your own research, make your own decisions, and do what you feel is best for your car and wallet. A word of advice, though: don’t piecemeal shit together. Remember, you want your car to perform perfectly at speed with parts that were made to work in conjunction with each other. Another thing to keep in mind: this is NOT a cheap hobby, so be prepared to spend some money. If you’re not seriously autocrossing or regularly tracking your car, there is no reason to go as extreme as I did.

Stage 1: CorteX Xtreme-Grip Suspension System
• JRi Double Adjustable, Coil over, Front Struts, $2495
• Offset Strut Option for 315mm tires, $99
• JRi Double Adjustable, Coil over, Rear Shocks, $2195
• Watts Link System, Street, $995
• Rear LCA System, Street, $569
• Torque Arm System, $995
• Bump Steer Kit, S197 Mustang, $179
• 3-Position Adjustable Anti Roll Bar, $279
• Anti-roll Bar Link, Adjustable, $119
• Drop Ball Joints $199

Total Stage 1: $8124.00

Result: A complete transformation in handling. Body roll was completely dialed out, initial turn-in was lightning-quick and I could now effortlessly rotate the car through the corner. Full-throttle corner exits were also drastically improved as the rear now lies flat thanks to the watts link and torque arm system. Power could also be laid down without the rear end wanting to come around. Dialing everything in now meant obtaining close to three degrees of negative camber up front. Once completed, the car was corner-weighted and balanced to the tune of 3,818 lbs.

Regarding lap times (because I know you’ll ask), my previous best around Laguna Seca was a 1:48 flat. With the Stage 1 kit, I dropped close to four seconds a lap whilst still running on street tires, the stock Brembo brakes with Hawk HP + pads and stock rotors. If there were any cons after the Stage 1 installs, it was that I was now in desperate need of brakes, more rubber, and a harness to hold me in place.

Stage 2: Cortex Racing Cage, Wheels, Tires, and Brakes
• 4-point Bolt or Weld in Roll Cage, $1595
• Stoptech STR40 355 x 35mm, S197 Spec Mustang Brake System, $3950
• Jongbloed 18 x 10.5, +45mm, one-piece wheels, $1700
• Ford Racing Mustang Brake Duct Kit 13-14 GT/Boss, $459
• Tow bumper, front, includes tow loop and splitter strut mounts, CorteX Design, $275
• Tow bumper, rear, includes tow loop, CorteX Design, $275
• 315/30/R18 Track tires: Varies per manufacturer
• 4-point harness (2), $600

Total Stage 2: $8,854.00 + $1,100.00-$1,600.00 depending on tires

Result: We decided to permanently remove the rear seats and weld in the cage for enhanced safety. Then we went with the Stoptech Spec Mustang Brake System with STR40 calipers and Ford racing brake ducts. The results of which were AMAZING! If you track your car, this is a MUST DO. I’m still in awe of how good these binders are. Zero brake fade, zero loss in pedal feel, and stopping power that’s on par with some of the best cars money can buy.

As for wheels and tires, I now run a 315/30/18 squared setup on Jongbloed 18 x 10.5 wheels under stock bodywork (Falken Azenis 615k tires). This is where the Cortex engineering comes into play as their kit was designed to accept a 315 front tire with no rubbing or spacers. The car now has so much grip that I had to adjust my driving style to compensate for the improved handling and turn in. To be honest, from a handling perspective, the car is now an animal that will run with just about everything.

Porsche GT3? No problem. Corvette Z06? No problem. Camaro ZL1? Again, no problem (although I haven’t come up against a Z/28 yet).

Is that a big statement? Yep, you bet, but I’ve run all of those cars on track at speed, and I am familiar with their handling characteristics. Aside from being down on power, this little Mustang GT will hang with all of them, but at a much cheaper price point. The limiting factor now is only the guy behind the wheel (me).

Stage 3: Shifter, Cooling, and Tune
• MGW Short throw shifter, $385
• Fluidyne 3 row Radiator Upgrade, $469
• Ford Racing Boss 302S ABS module, $349
• K&N CAI, $365
• 91-octane custom tune, $300

Total Stage 3: $1868

Result: No idea – I haven’t done it yet. I need to save up more moola.

Here’s the deal: My goal, even before I made my initial purchase of the Mustang, was to have a car that was capable of going after some of the best cars out there, but to be all-in financially for under $50,000.

Have I succeeded? Absolutely.

• 2013 Mustang GT 300A base model w/track pack (bought new): $31,600.00
• Cortex Stages 1 & 2: $18,669.00

Total: $49,669.00

Is that a lot of money? Yes, but who says you must buy a new car, and who says you need to do everything at once? Used S-197 Mustangs from 2005 and up can be purchased for around $12-15k now depending on the mileage and condition. They’re amazing platforms, and as shown, can be turned into giant killers when set up properly. Do yourself a favor, though: if and when you decide to pull the trigger on modifying your Mustang (or any other car for that matter), get educated and do it right. Doing it wrong can open up a can of worms you’d never want to deal with.

Post up questions/comments in the forum and I’ll try and answer as many as I can! >>