Ford GT fi­nally shows us what it can do to our in­ter­nal or­gans when it turns a wheel un­der its own power

San Francisco Chronicle - - CARS - By Eric Ting­wall

Lap after lap, Scott Maxwell gnaws deeper into the curb­ing. By draw­ing a straighter line through a shal­low chi­cane on the road course that lies in the shadow of Las Ve­gas Mo­tor Speed­way, the Cana­dian pro driver with class wins at Se­bring, Day­tona, and Le Mans is search­ing for — and find­ing — more speed. What started as a nib­ble is now a chomp as he rides to the top of the red-and-white candy cane on his fourth lap. The 2017 Ford GT he’s pi­lot­ing, the car in which I’m rid­ing shot­gun, swal­lows it whole.

The GT skates over the pave­ment, clear­ing it by just 2.8 inches in its ground-suck­ing Track mode, when the Miche­lin Pi­lot Sport Cup 2 tires are sunk into the wheel wells and the GT looks as if it has all the sus­pen­sion travel of a bob­sled. Yet this car­bon-fiber dart from Dear­born never threat­ens to lose trac­tion, to pitch left, or to un­set­tle as it leaps off the curbs. It soaks up the in­put grace­fully, presses rub­ber into earth, and rock­ets ahead. “I kept ex­pect­ing that curb to launch us,” Maxwell says dur­ing the cool-down lap. “But the car just takes it.”

The skyscrap­ing wing/air brake rolls out a Gur­ney flap from its trail­ing edge when de­ployed, while a pair of ac­tive shut­ters stalls air over the front split­ter to bal­ance the to­tal down­force. Hameedi won’t cite ex­act num­bers for the GT’s per­for­mance in that area. He fig­ures that data would al­low the com­pe­ti­tion to make an easy ex­trap­o­la­tion to the race car. “We still want to win some more races,” he says.

Both Maxwell and White ex­tol the ben­e­fits of the GT’s down­force as they lap, but those virtues aren’t as tan­gi­ble from the pas­sen­ger seat. It’s the un­con­ven­tional sus­pen­sion and its ef­fi­cacy that are rewiring my brain. There are no coil-overs. In­stead, at each corner, the sus­pen­sion pushrod trans­fers the lower con­trol arm’s move­ments to a rocker arm that con­nects to the damper and an­tiroll bar while also twist­ing a splined tor­sion-bar spring. The op­po­site end of the tor­sion bar, in­stead of be­ing fixed to the body, at­taches to a hy­draulic ac­tu­a­tor that con­tains a small coil spring, al­low­ing Ford to vary the spring rates de­pend­ing on the driv­ing mode. Act­ing in se­ries with the tor­sion bar, this coil pro­vides a softer over­all spring rate in the car’s Wet, Nor­mal, and Sport modes than the tor­sion bar alone pro­vides.

The hy­draulic ac­tu­a­tor comes alive in the Track and V-Max modes, com­press­ing the coil spring and drop­ping the car two inches. In th­ese set­tings, the coil is locked out, in­creas­ing the

over­all spring rate. Push the but­ton to con­firm, and the sus­pen­sion doesn’t de­flate as in an air-spring car; rather, it pops into a squat abruptly, a Le Mans racer drop­ping off its air jacks in the pits.

Mul­ti­matic, the Cana­dian sup­plier and com­pos­ites ex­pert that builds the GT in a sub­urb of Toronto, sup­plies the spool-valve dampers that deftly blend com­pli­ance and con­trol. Th­ese de­vices of­fer finer tun­ing pre­ci­sion than the stacked shims that con­trol damp­ing rates in a tra­di­tional damper, and for the first time they are elec­tron­i­cally ad­justable via a ro­tat­ing sleeve that opens and closes cer­tain tai­lor-shaped ports in the spool valve.

The twin-tur­bocharged 3.5liter V-6 is a close rel­a­tive of the 450-hp ver­sion in the F-150 Rap­tor. En­gi­neers un­locked an­other 197 horse­power with a lower 9.0:1 com­pres­sion ra­tio, larger tur­bocharg­ers, and new man­i­folds, while a dry-sump oil­ing sys­tem keeps it all lu­bri­cated on the track. En­gi­neers also re­lo­cated the al­ter­na­tor and air-con­di­tion­ing com­pres­sor to the back of the en­gine to lo­cate it closer to the fire­wall, shift­ing the cen­ter of grav­ity and re­duc­ing the po­lar mo­ment of in­er­tia.

The EcoBoost en­gine sucks in clean air from the lower por­tion of the side pods ahead of the rear wheels. The tur­bos pres­sur­ize the in­take charge up to 30.0 psi and pass the air back to the side pods, where it climbs through the in­ter­cool­ers and is piped through the but­tresses to­ward the roof, then down into the in­take plenum. Both port and di­rect in­jec­tion de­liver the fuel.

The big blow­ers mean that the peak torque of 550 pound­feet ar­rives at a very lofty, un-turbo-like 5900 rpm. To keep the tur­bos on call when the driver lifts off the ac­cel­er­a­tor, Ford ac­ti­vates an anti-lag sys­tem in the Sport, Track, and V-Max modes. By con­tin­u­ing to pump some air through the en­gine, the tur­bos turn at about 80,000 rpm off throt­tle. At full boost, they pin­wheel at up to 176,000 rpm. That anti-lag sys­tem is just one in­di­ca­tor that Ford pri­or­i­tized Boost well ahead of Eco with this en­gine. The other tell­tale: the GT’s glut­tonous EPA com­bined rat­ing of just 14 mpg, only two ticks bet­ter than the nat­u­rally as­pi­rated V-12 Aven­ta­dor S.

While the GT’s V-6 de­liv­ers su­per­car thrust, a car with looks and moves that can snap necks de­serves the au­ral drama of eight, 10, or 12 cylin­ders. The EcoBoost en­gine’s sound­track is loud and deep, but it’s a thrum, not a bark or a scream, with no fire and brim­stone rain­ing from the ex­haust. The GT’s en­gine sounds awe­some for a V-6 Fu­sion but re­strained for a 647-hp su­per­car. That’s the down­side to mak­ing your power with six pots muf­fled by two tur­bocharg­ers, but Ford landed on that con­fig­u­ra­tion, it says, specif­i­cally for the fuel-econ­omy ben­e­fit in the race car. And, no doubt, the mar­ket­ing trac­tion the EcoBoost as­so­ci­a­tion buys.

The road car routes torque to the rear wheels through a Ge­trag seven-speed dual-clutch trans­mis­sion and a Torsen-style lim­ited-slip dif­fer­en­tial. In man­ual mode, cogs are swapped via milled-alu­minum shift pad­dles in­spired by the Day­tona pro­to­types in which Ford de­vel­oped the GT racer’s en­gine be­fore the rest of the car was fin­ished. The stack of slots in the pad­dles and the ver­ti­cal ridge on their back­sides add tac­til­ity and grip. Launch con­trol — ac­ti­vated from the top line in the dig­i­tal in­stru­ment clus­ter’s menu — cues the en­gine at roughly 3000 rpm and should send the 3250pound GT to 60 mph in un­der three sec­onds. With V-Max mode re­tract­ing the wing and open­ing the two flaps at the back edge of the front split­ter to re­duce drag, this car­bon-fiber won­der ran a claimed 216 mph at Porsche’s Nardò test track in Italy.

To­day we’ll top out at 135 mph while driv­ing around what White, the chas­sis engi­neer, calls a “lit­tle Mickey Mouse point-and-shoot thing.” The road course at Las Ve­gas Mo­tor Speed­way is ut­terly flat, a gokart track on a grander scale. Nev­er­the­less, in a Ford GT, the thrills are more Space Moun­tain than Dumbo the Fly­ing Ele­phant.

2017 Ford GT Es­ti­mated base price: $450,000 Zero to 60 mph: 2.9 sec Top speed: 216 mph EPA com­bined/city/ hwy: 14/11/18 mpg

FORD

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