CAR and Driver - March 2017

CURB WEIGHT,

LB

ROADHOLDING, 300-FT-DIA

FT70–0 BRAKING, SKIDPAD, G

SECACCELERATION, 0–60

1/4-MILE

ACCELERATION,

SEC

BASE PRICE†,

$ X 1000 HORSEPOWER

SOUND LEVEL, dBAWIDE-OPEN-THROTTLE

3.0 3.5 4.0 4.5

155

150

145

140

11.5

12.0

12.5

13.0

65

70

75

80

400

500

600

700

95 90 85 80

1.10

1.05

1.00

(^4500) 0.95
4200
3900
3600
BMW M4
3.0-L I-6, 7-SP AUTO
CHEVROLET
CAMARO ZL1
6.2-L V-8, 10-SP AUTO
DODGE
CHALLENGER SRT
HELLCAT
6.2-L V-8, 8-SP AUTO
FORD MUSTANG
SHELBY GT350R
5.2-L V-8, 6-SP MAN
†Includes
performance-enhancing
options.
Who ever said America
wasn’t great?
—
COMPETITORS
059
ROLLING START, 5–60 MPH .................................. 3.9
TOP GEAR, 30–50 MPH .......................................... 1.8
TOP GEAR, 50–70 MPH ........................................... 2.1
1/4-MILE ....................................... 11.5 sec @ 125 mph
TOP SPEED ....................... 195 mph (drag ltd, C/D est)
HANDLING
ROADHOLDING, 300-FT-DIA SKIDPAD .......... 1.04 g
UNDERSTEER ................................................. Moderate
BRAKING, 70-TO-ZERO MPH
SHORTEST STOP ................................................. 143 ft
LONGEST STOP .................................................... 162 ft
FADE R ATING ......................................................... None
WEIGHT
CURB ................................................................... 3933 lb
PER HORSEPOWER ............................................... 6.1 lb
DISTRIBUTION ............................... F: 54.5% R: 45.5%
TOWING CAPACITY ................................................. 0 lb
FUEL
CAPACIT Y ........................................................... 19.0 gal
OCTANE ...................................................... 91 (required)
EPA COMBINED/CITY/HWY .............. 18/15/22 mpg
(C/D est)
C/D OBSERVED ................................................. 13 mpg
INTERIOR SOUND LEVEL
IDLE ....................................................................... 46 dBA
FULL THROTTLE ................................................. 95 dBA
70-MPH CRUISING ............................................ 69 dBA
The 10-speed automatics
in the Ford F-150 Raptor and
the Camaro ZL1 originate
from the same base gearbox,
the product of a collaboration
between the two American auto-
makers. While Ford led the development
of the 10R transmission, GM engineers
refined the Hydra-Matic 10R90 for use in
the company’s high-output powertrains.
Hydra-Matic–specific pieces include the
torque converter, clutch components,
planetary gear carriers, and bearing
supports, all uprated to cope with the LT4
V-8’s 650 pound-feet of torque.
All 10R transmissions get their 10
ratios from four planetary gearsets selec-
tively controlled with six clutches—four
that rotate and two that act as brakes. The
transmission case slips into the same
space as GM’s longitudinal eight-speed,
which fits into the same space as the
six-speed before it.
You might expect the industry’s first
10-speed transmission to boast a gaping
overall ratio spread, but the 10R’s 7.38:1
range is far from the widest in the
business. Among longitudinal automatic
Explained:
Hydra-Matic
10R90
Automatic
Transmission
The team that built the ZL1 pitches
the car as equally adept at running quar-
ter-mile drags, lapping Virginia Interna-
tional Raceway, or writhing along the
Angeles Crest Highway. It’s certainly com-
petent at any of those activities, but we
think it’s truly exceptional at the last one,
streaking down a great road and plastering
a grin on your face. Strapped into the
deeply bolstered Recaros by red seatbelts
(standard with select exterior colors),
we hammered the ZL1 over the highway
through the San Gabriel Mountains north
of Los Angeles, confident in its firm brake
pedal and natural steering, the trans auto-
matically holding the lowest gear, and the
engine blasting anger through the valleys.
Few things have made us happier this year.
We weren’t offered a chance to drive the
ZL1 convertible, so we can’t say if Chev y
has done anything to stiffen that rolling
tub of Jell-O. The coupe, however, has no
trouble managing the engine’s grunt, the
road’s imperfections, and the considerable
cornering forces the ZL1 can muster.
With the Camaro ZL1, Chevrolet mixes
its most raucous, most capable hardware
into a monster of a car at a bargain price.
More tire and less weight could turn it into
a true track rat, but it’s a car that you can
live with every day and hustle across any
piece of pavement, and we wouldn’t change
a thing. The ZL1 is even greater than the
sum of its special parts.
transmissions, that spread is topped
by ZF’s second-generation eight-speed
8HP, and both seven- and eight-speed
versions of Porsche’s PDK for front-engine
vehicles, the latter of which has a yawning
11.26:1 spread.
Engineers say there’d be little benefit to
stretching the ratio spread given the 10R’s
intended applications. The ZL1 lights up its
tires at less than full throttle in first gear,
and the LT4 turns over at less than 1900
rpm in 10th gear at 80 mph. Instead, the
10R packs its ratios closer together, with
upshifts averaging a 19 percent drop in rpm
versus 29 percent in the eight-cog PDK.
That keeps the engine closer to its power
peak throughout full-throttle acceleration
runs, and this keeps us happy. —ET