by Rod Short
photography by the author
Super Ford, August 1996, pp 90-91
Attention to air flow and a set of gears put this SC into the 13s
For some enthusiast's, the ideas of non-V8 performance intrudes
into their comfort zone. However, Bill Hull of Charlottesville, Virginia,
challenges that notion with his 3.8 liter V6 1991 Super Coupe. With elapsed
times in the mid-13s this daily driver shows it doesn't always take eight
cylinders to fly.
"I had always considered a car with less than eight
cylinders as fit for only little old ladies and 97 lb weaklings,"
Hull recounted. "I went down to my local Ford dealership intent on
ordering a '91 Mustang GT. One of the salesmen had a Super Coupe and, while
I'd liked the car's looks, I still didn't care for the V6. However, I went
on and drove it, found that the ride was fantastic and that it had decent
power, so I just went on and ordered the Super Coupe."
It's too bad more folks didn't follow Bill's lead. Super
Coupe production reached just 49,917 cars over a six-year lifespan, not
enough to keep the combination going. The last version smoked off the showroom
floor rated at 230 hp and 330 lb ft of torque at 4000 rpm. This compares
favorably, if there is any comparison, with the Thunderbird LX V8's 205
hp, 256 lb ft of torque at 4200 rpm with the smooth but slumbering modular 4.6 V8.
With 15 more lb ft of torque that the 5.0 HO engine, Super
Coupes were already fun on the street with a great ride comfort and sophisticated
handling from the MN12 chassis, but Hull couldn't resist tweaking his black
bird 'Bird just a little bit.
"I've always liked a challenge and, with Mustangs
being so popular, I wanted to see if I could get this 3800 lb car to run,"
Hull said with a smile. "But, I found out that no one knew anything
about these cars and that high-performance shops didn't have time for folks
like us, unless we had a Mustang. It was real frustrating. There was a
guy in Florida, however, that had spent a lot of money to build one up professionally
and had advertised everything for sale after throwing a rod in his engine.
So, I went down there and brought it back in pieces. He had done a lot of
the groundwork, but I added a lot of stuff of my own and probably spent
a $1000 in phone calls getting ideas to put to use."
Bruce Baker of Express Automotive in Deland, Florida,
did the machine work, opening the original 3.81-inch bore by .030-inch
and O-ringing the block. Ronnie's Auto Service and Walker's Auto Parts
& Machine, both of Charlottesville, Virginia, did the rest of the work
with the pieces Hull brought home.
After some massaging, the bottom end was reassembled and
mated to the stock cylinder heads, which had been ported. Stainless steel
Manley 1.80 x 1.60-inch valves were used. The valvetrain is all-Crane,
featuring a cam producing 206 degrees of duration at .050 inches of lift,
.509 inches of valve lift via 1.73 ratio rockers, dual springs, titanium
retainers and 5/16-inch pushrods. Hardened valve seats, bronze guides and
hardened keepers provide extra durability.
The key to the Super Coupe's 3.8 liter performance is
in the induction system and extra attention there made Bill's combination
even better. The intake, manifold adapter and intercooler tube were Extrude
Honed, gasket matched and joined with a set of Lucas 38 lb hr injectors,
SVO 155 lph fuel pump, Cartech boost-controlled fuel management unit and
BBK 70mm throttle body. Jerry Magnuson, who distributes Eaton superchargers,
replaced the M-90 roots blower with a 2.5:1 overdrive ratio S blower. This
yields 13 lbs of boost. A Spearco intercooler and manually-switched electronic
fan keep a handle on cooling.
A key modification involved the supercharger adapter air
outlet which was raised, enlarged and polished for better airflow. Switching
to a slightly-raised Cervini fiberglass hood allowed this modification
as the stock hood doesn't provide enough clearance, thus forcing a more
restrictive design for the stock Super Coupe. Hull believes that not addressing
this area makes any modification, in front of or behind this, much less effective.
Finishing touches include JBA 1 5/8-inch diameter shorty
headers and an MSD ignition. As for chassis and powertrain mods to accept
the increased power, an AOD automatic, 4.10 gears in the 8.8-inch axle
and Cougar alloy rims shod with BFGoodrich TA's help put the torque to pavement.
Whereas stock, automatic Super Coupes usually quarter
mile around 16 flat at 89 mph, Hull's latest drag strip outing produced
a 13.50 ET at 101 mph. This was at a hulking 4000 lbs with driver on street
tires, which whiz-wheels out to 325 hp. Call it 1.4 hp/inch, or pretty
good--the same efficiency would yield a 428 hp 302.
Hull's experience and enthusiasm for these cars led him
to found the Super Coupe Club of America which has been stirring some interest.
"All the people calling me about the club say the same thing, almost
to a person," Hull remarked. "they love these cars but nobody,
even the dealer, knows anything about them. People want to trade them because
they think no one makes anything for these cars and because they can't
even see the motor when they open the hood. When you get into it by taking
the blower and intercooler off, you basically have just a V6. There are
a lot of parts available, but it's just not commonly known."
While the Super Coupe is unfortunately now out of production,
realization of their performance potential may long preserve their memory.
3172 Bunsen Ave., #K
Ventura, CA 93003
14664 Titus St.
Panorama City, CA 91404
Super Coupe Club of America
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