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VIDEO: 2015 Ford Mustang GT 5.0 Drag Test - How to Get the Most Performance Out of the S550
Our tips for getting the most performance from the 2015 Mustang GT
The time-honored question car enthusiasts often ask is undoubtedly, “What will it run?” Meaning, how quickly can a given car cover the quarter-mile. Drag racing is universal and allows us to compare cars and driver skill no matter where in the world the car is raced. Sure, a great ’Ring time is important, but how many of us will travel to Germany to race? Going quick in the quarter (or eighth-mile) requires a favorable power-to-weight ratio, good traction, and some driver skill. With the 2015 GT, you get 435 ponies and the weight is about 3,750 pounds. So, what will it run and how will the IRS perform on the strip?
The all-new Mustang has garnered rave reviews from editors and critics for the enhancements in handling. The suspension provides amazing compliance and has better balance than any Mustang to come before, but what about straight-line acceleration? What’s it like to do a burnout, launch, and powershift your way down quarter-mile? Will there be wheelhop, broken half-shafts, and scattered differentials?
We spent a week with this yellow screamer hitting all the local hot spots, including Bradenton Motorsports Park, home of the NMRA Spring Break Shootout. Our GT was equipped with the standard rear gear (not 3.73s) along with the Getrag MT-82 six-speed, and we ran the car 100 percent stock—so no drag radials or tune. Heck, we didn’t even cool the engine! Traction was good, but the temperature was 84 degrees with mild humidity—not mineshaft conditions, by any means, but not sweltering either. Based on our experience we were hoping to break in the 12s at about 110 mph.
The 2015 is comfortable and nimble on the street. It has good power and a great sound too. We were anxious to get on track, do a real burnout, and launch on a prepped surface. What we found is that the 2015 Mustang is tricky to launch compared to the out-going S197 Mustang. Why? In layman’s terms, the live axle in the S197, which is considered somewhat crude, provides great feedback for drag racing. The three-link suspension does a fantastic job of planting the tires and transferring the torque loads to the body to create pitch rotation (nose lift) to transfer weight from front to back. The heavy axle assembly also gives lots of feedback to the driver and really communicates what the tires are doing.
You can feel slight chirping or slipping of the tires and apply power and clutch accordingly to get maximum traction and acceleration. The IRS provides excellent grip on launch, but it also reduces some of that feel because the tires are more isolated from the chassis. Because of this, it’s harder to feel exactly what the car is doing, which is important when you’re on the ragged edge of slip or grip. This forced us to drive more conservatively to find consistency. Of course, this wouldn’t be a problem with drag radials or slicks.
In addition to giving you the scoop on our quarter-mile times, we figured we would include our driving technique and offer a few tips so you can get the most from your Mustang. This can be applied to any Mustang, old or new, stick or auto. Ultimately, your best times will come once you’ve refined your driving technique and your talent in regards to burnout, staging, launching, and shifting. Let’s begin with the burnout.
Some will tell you burnouts are unnecessary when driving on stock tires, we disagree. Why? Because tires pick up pebbles and debris, especially in the pits at a race track. If you try to launch with all this crud on your tires, you’ll probably spin. It’s like running on marbles. You can imagine how that would end. Doing a burnout, even a short one, cleans the tires and offers the best rubber-to-rubber contact. We recommend doing only enough of a burnout to clean the tires, as street tires don’t really react like slicks or drag radials. Don’t sit there and smoke ’em too long, or you will draw the oils from within the tire to the surface and that will actually make them slick, not sticky.
The 2015 GT is equipped with a Line-Lock, so doing a burnout is pretty easy. Be sure to roll all the way through the water box (or go around it) then stop. Refrain from doing a burnout in the puddle of water . . . and don’t roll too far out of the water box, either, because that would put you in the really sticky stuff, and doing a burnout there can hurt your clutch. You want to be right on the fringe of the puddle, just in front of it. If you have 3.73 gears (or numerically higher gears) do the burnout in Second gear. With 3.55s or less, use First. The idea is to create wheel speed, as this gets the tires cleaned quickly, without putting too much load on the clutch. And please don’t upshift with a stick in the burnout. Why? When you step on the clutch to shift the tires stop, and since they are already sticky, it’s hard for them to get going again and this will wreak havoc on your clutch. Yes, Pro Stock drivers upshift in the burnout, but they use a clutchless trans.
To get started, select “Line Lock” in the Track Apps and follow the prompts. Once engaged, you get 15 seconds to smoke the tires—but you probably only need a third or half that time to get the job done. Be sure you have the engine revved above 4,000 when you dump the clutch; this will prevent the engine from bogging and overloading the clutch. Also, keep the rpm steady, as this will keep the Traction-Lok rear engaged properly. Floating the throttle can cause the dreaded one-wheel peel. Once you have the tires clean and warm (you can see if they are smoking by aiming your side mirrors at the rear tires), drive out of the burnout under power. This helps get rid of any residual water, and it’s fun.
You can also attack the burnout using the old-school method. Set up in the same fashion, but instead of using the Line-Lock, rev it up, dump the clutch, and quickly grab the brake pedal with you left foot. The trick is to use only sufficient brake pressure to hold the car. That’s because rear brakes will be applied, so using this technique will wear your rear brakes prematurely.
We noticed a slight amount of wheelhop when doing a burnout in the 2015 Mustang. This seems to be common, but it can be reduced with stiffer rear bushing. In the name of proper reporting, we tried doing burnouts both ways and found both methods to be effective.
Just remember, the burnout prepares the tires for launch, nothing more, nothing less—and your first launch will give you the most traction. For that reason we don’t recommend dry hops or practice launches once you’ve done your burnout. Simply engage First gear, roll up slowly, prestage, and STOP!
Staging for E.T.
If you’re looking for a good elapsed time, shallow staging is a must. Prestage, stop, collect yourself, and then carefully inch forward until you barely turn on the Stage beam. I’ve seen lots of racers dump the car in both beams in one motion, which usually results in the car being “deep” staged. Since your time starts when your front tires break the stage beam, shallow staging gives you a running start on the timing system. Shallow versus deep can be worth as much as two-tenths of a second!
Launch It—Two Ways
Certain models of the 2015 Mustang have Launch Control. You can use this driver aid or do everything yourself. Either method requires a cool head on the line and smooth release of the clutch. Once you’re staged, your adrenaline will be pumping and you’ll be itching to unleash all that power. Launching on street tires is tricky, so your full concentration will be required.
While the drag racing launch can be violent (we’ve all seen racers dump the clutch and blast off the line), street tires require a smooth, controlled application of power to stay hooked. Your best times will come from getting off the line clean. Finesse is key. Believe it or not, we recommend novice drivers launch as if they were driving away from a traffic light, but with more rpm and slightly quicker clutch release. We would say 2,500 is a great place to start. Using this rpm, you’ll probably bog the engine a bit. No problem—add rpm, or get the clutch out quicker.
We use the release-pause-release method, and it works really well. Let us explain. Since you don’t have a huge sidewall (like slicks have) to absorb the initial “hit” during launch, you’ll need to create a buffer to absorb the initial movement at the tires. If you don’t have a buffer, you’ll just spin. When it’s time to go, release the clutch quickly, but controlled. Then, just as the car is transferring weight, pause your left leg for a moment. When the maximum weight has been transferred to the rear, feed in throttle and let the clutch out smoothly. In the 2015, we used between 3,000 and 4,000 rpm and applied our technique to record a 2.10 60-foot time. No doubt with more practice it could have been whittled down. In fact, you can watch the drag test video at our network site, mustang-360.com.
In Launch Control mode, follow the prompts to set up your rpm. Once you’ve staged you can put the throttle on the floor and keep it there for launch, or for the entire run if you’re powershifting. When you step off the clutch to launch, the Mustang will do its best to give you maximum acceleration. Using Launch Control still requires a smooth release of the clutch to give you the best performance. While the system allows some spin, excessive spin will cause the computer to apply rear brake and kill a bit of power to regain traction.
Powershift for E.T.
Enthusiasts will tell you there are three types of shifting: granny, speed, and power. Simply stated, if you shift aggressively but lift off the gas, you’re speed shifting. If you ram the gears with the throttle held on the mat, you’re powershifting. Granny shifting is not worth talking about. In any case, you want to complete the shift as quickly as possible and with as little flare in the rpm. Timing is everything. Practice makes perfect. If you’re uncomfortable powershifting, try it at a lower rpm until your shifting is seamless.
Our technique in the 2015 GT is the same as in previous Mustangs. We find an upright driving position to get good leverage on the shifter, and keep our hand on the shifter during launch so we’re ready to go.
Start by remaining focused on the tach and listen to the engine—most times we have a specific rpm in mind, but generally we shift by feel. Naturally, you want to shift before the engine hits the rev limiter, but with the Coyote engine you want to get close to redline. In the 2015 we were shooting for 7,000 rpm.
We tend to preload the shifter just a bit, then stab the clutch and rip the shifter. We repositioned our hand from a side grip to a top grip to ram the shifter forward for the Two-to-Three exchange. In the new GT you’re shoving it almost directly forward—aim too much to the right and you’ll find Fifth, which happened to us twice. Then, get ready to pull straight back for Fourth. For Fourth, put your elbow away from your body to prevent yanking the shifter into Second gear.
Once in Fourth, all that’s left is to ride it out. With 3.73 and a few mods, it may be necessary to upshift one more time into Fifth. This always makes us nervous because we don’t want to mess up the last shift, plus Fifth gear can be fragile and we don’t want to break the trans. Our test car did not require shifting into Fifth, but we’ve had to do so in 2011-2014 5.0 Mustangs.
We ended up with a few 13.0 runs and a best of 12.94 at 112.58. It took a little longer than we anticipated to find the sweet spot for launching. As always, more time would have equaled better e.t.’s. In the end, our best run came from revving the 5.0 to approximately 3,200 rpm, and by releasing the clutch smoothly and rolling the throttle to the floor, rather than smashing it open. Drag radials and 3.73s would have gotten us in the 12.50s or 12.60s, based on the mph.
We are pleased with the performance of the 2015 Ford Mustang GT. It takes time to get the best performance from any new combination, but if you utilize the driver aids such as Line-Lock and Launch Control, you’ll get up to speed quickly. Ford has done a wonderful job providing the necessary power and technology to make this one heck of a Mustang. There’s more latitude in finding a good driving position, the seats are better, and the overall feel of the car is world-class. And there’s a host of aftermarket goodies if you’re looking for more. We would most certainly recommend the 3.73s for anyone planning to hit the strip, along with a set of drag radials.
The Mustang was a blast at the track. Even famous author Stephen King, who happened to be at the track, came over for a look. He didn’t think it was too scary, so we doubt it will appear in his next book, but you never know. He has written about a car or two in the past.