2015 Ford Mustang EcoBoost 2.3 First Ride
"Flat" is a word that keeps coming up as the vehicle dynamics engineer at the helm of the 2015 Ford Mustang EcoBoost describes the results of his work fettling on this pending pony’s new suspenders. It corners flatter, it brakes a lot flatter, and it’s just a much more buttoned-down car -- at least to hear him tell it. We’re in the sprawling parking lot outside the zMAX Dragway, across the street from Charlotte Motor Speedway, threading the cones of a moderate-speed autocross course. Indeed, the view and sensations coming through the right chair give little cause for argument, and there’s plenty of good reason to expect such results based on the engineering design.
This 2015 Mustang, the first that any journalists have gotten a ride in yet, is (almost) the nimblest package that will be offered -- 305-plus horses from the 2.3-liter turbo and the performance package, but the six-speed paddle-shifted automatic is probably not the nimblest transmission. It’s a good choice for this exercise, though, as I can sense the way the shift schedule changes as my chauffeur toggles between the Normal/Sport/Track modes better than I could have perceived clutch takeup and shifter feel without using my own limbs.
That track package eliminates all rubber from the front suspension links responsible for transmitting lateral forces from the tires to the chassis, replacing them with metal-to-metal ball joints. The suspension cradle to which they are attached is also un-isolated, all of which makes for more immediate reactions to steering inputs, and (theoretically) more feedback through the adjustable electric-assist steering. (It’s supplied by the same folks who made the Boss 302’s rack.) There’s more magic in the suspension geometry, made possible in part by the front struts’ double ball-joint lower attachment. This produces a “virtual” steering axis in the form of a cone that has the effect of moving the effective steering axis point further outboard, increasing road feel.
Whether jinking through a lane-change or slalom event or accelerating through a broader sweeper, the 2015 Mustang EcoBoost’s body does seem to maintain a reasonably even keel -- a sensation backed up by watching laps trackside. Overall grip from the 255/40R-19 Pirelli P Zero summer tires also felt appropriately sporting, and the limits we approached produced minimal squeal.
That double ball-joint setup also frees up space for big brakes without increasing wheel offset. Performance package brakes here measure 13.9 inches in front, clamped by four-piston fixed calipers (just about like on the 2014 Mustang GT Track or Brembo Brake packages). Rears are 13.0-inch vented. The independent “integral-link” rear suspension permits way more anti-dive geometry than anyone’s live axle could, which is the biggest contributor to the flatter braking. Working together, the front and rear suspension resist dive, squat, and lift twice as well as before.
One burning question that goes unanswered for yet another 2015 Mustang program is mass. The only clue we got was an admonition against counting on the I-4 weighing a whole lot less than the base aluminum V-6. It will, however, reach peak torque way lower in the rev range, meaning that even if it doesn’t produce much more than the 305 hp the V-6 does, it should very easily outrun that car. It certainly seemed to move out every bit as smartly as a 2014 Mustang V-6, thanks in some part to the performance package’s 3.55:1 axle ratio. That axle is optional on the 2015 Mustang V-6 and 2015 Mustang EcoBoost I-4, with 3.15:1 the base axle on both. (The 2014 V-6 made do with 2.73:1 or 3.31:1, the latter of which will also be offered on the 2015 I-4.) Folks interested in optimizing their EcoBoost Mustangs for autocross circuits like this (and not CAFE optimization) might try fitting a 3.73:1 axle, which we’re told will be offered on the V-8, though it doesn’t show up on the spec sheets yet. In the Track transmission mode, lower gears seemed to hold nicely while braking into the big sweeper, and the box’s reaction to paddle inputs seemed quite instantaneous. In that mode, a manual gear selection pretty much holds no matter what, resting on a smooth rev limiter if you insist.
The engine note of the 2015 Mustang EcoBoost sounded pleasingly snarly -- which isn’t easy with a turbo muffling the exhaust -- though final sound tuning has yet to be completed. When it is, the sound reaching your ears will be a symphonic composition of genuine intake and exhaust frequencies enhanced by nice noises piped in through a sound pipe and objectionable ones erased via active noise cancelation. That’s about all we can tell you at this point, but rest assured the Chinese water-torture dribbled release of ponycar info will continue right on through the promised full-on drive programs later this year.