car typically has a strong chassis, great
brakes, plenty of power, room for two,
decent luggage space and quasi-racer
details.
Rosen reasoned that the Corvette had
the best chassis, suspension, brakes and
engine combo of any American auto-
mobile. Therefore, Rosen’s GT machine
started where the Phase III ended. All
of the mechanicals were essentially the
same, with the later addition of a Hone
Overdrive to improve highway cruising.
Never happy with the new Corvette’s
pop-up headlights, Rosen designed new
front fenders with the headlights tun-
neled into the fenders and covered with
plexiglass; illegal, but very cool-looking.
What made the biggest difference was
the fastback rear window. While not
totally restyled, the flat rear glass laid
just below the leading edge of the C3
coupe’s side roofline. Even Duntov liked
the design and congratulated Rosen on
getting done what he couldn’t. Phase III
GT Corvettes had a lot of custom body-
work and most sold for over $12,000;
double the cost of a new Corvette.
Motion Maco Corvette
Not everyone was thrilled with the
new Corvette. The August 1967 issue
of Motor Trend featured artwork of the
all-new ’68 Corvette looking just like
the Mako Shark-II. John Silva was a car
customizer that decided to build a Mako
Shark-II body kit for the new Corvette.
According to the Scott Ross article,
“1976 Maco Shark II – Repro Mako” at
http://www.superchevy.com, Silva made 125
“Maco Sharks.” To avoid legal issues
with GM, Silva called his kits, “Maco
Shark” instead of “Mako Shark.”
Rosen reasoned that the quickest way
to get to a Motion Maco Shark was to
work a deal with Silva to pull molds
off a Silva Maco kit. The Maco Shark
was most likely never intended to be
an exact, precise replica of the run-
ning 1966 Mako Shark-II show car.
The kit had all the key features of the
original: the exaggerated fender humps,
the nose surface details, the Sting Ray-
like roof section, window slats and the
full tilt-forward front end. Under the
pretty fiberglass was an all-out Motion
Performance beast, tricked out to the
customer’s specifications. The Maco
Shark cars were a love-it-or-hate-it kind
of Corvette. Motion Performance and
Silva did the best builds.Motion Manta Ray Corvette
Once Rosen got his body shop up and
running, he was having too much fun,
mixing and matching custom body parts
for his Corvettes. The Motion Manta Ray
was part Phase III GT and part Motion
Maco with some factory designs thrown
in. Built on a 1973 Corvette with the first
of the soft bumper covers, the front end
has the Phase III GT’s tunneled-in head-
lights. Rather than a Phase III hood with
the ’67 Stinger scoop, the Manta Ray uses
a factory-style L88 hood and the front
end does not tilt forward. Hooker Header
side pipes adorn the side rockers. At the
back end, a Z28-style flipper spoiler is
grafted on to the rear deck and the full
Mako/Maco rear roof section, window
slats and all, completes the overall look.
The fuel filler was relocated to the driver’s
side of the rear deck and is finished with
a quick-fill GT cap. The Motion Manta
Ray Corvettes were only offered in 1973,
and just three were produced.This was the first Baldwin-Motion SS-427 Phase III Corvette. Chevrolet could have
done this as an appearance package for big-block 1968 and 1969 Corvettes. (Photo: K.
Scott Teeters’ Cars Archive)Rosen considered his Can Am Spyders to be his wildest Corvettes. IMSA widebody
kits on street Corvettes were often not well done. Rosen’s Can Am Spyder had the
stance, ride height and proportions just right. (Photo: K. Scott Teeters’ Cars Archive)Custom car builder John Silva hoped
that the 1968 Corvette would be more
like the 1966 Mako Shark-II Corvette
show car. So he made his own full body
kit for new Corvettes, the Silva Maco
Shark. Rosen worked a deal with Silva to
pull molds off the Silva parts so he could
offer his own Motion Macos. (Photo:
Martyn L. Schorr Archive)Rosen is on record saying, “I sure
wish I still had that red Can Am
Spyder.” (Photo: K. Scott Teeters’
Cars Archive)Adam Tuckman is a collector of Motion
Performance cars and currently owns
the Dr. Rollings 1971 Phase III GT 454 Cor-
vette. Back in the day, the good doctor
used to do house calls in this car. This
was the last of 12 Phase III GT Corvettes
that Rosen built. (Photo: Martyn L.
Schorr Archive)50 VETTE 19.09
[FEATURE]
PHASE III SUPERCARS