| TESTING TWO
TIGERS
continued
4- speed shifter seems more business like without
console. Wood wheel adds class.
Hurst Hydro-Shifter is available only with console, and
offers firm, positive shifts.
Storage area in console is easily reached from either of
the comfortable buckets. |
gave
firm, precise control at all times. Standard equipment Wide-Oval tires
plant themselves firmly to the road, do- ing their bit for good handling.
This car stopped like it had front-disc brakes but a quick look underneath
un- covered drums. Recalling the sad drum brakes on last year’s car, we
couldn’t get over how straight and quick the new ones worked in wet
weather and dry. It is one of the few cars we’d buy and not insist on
disc brakes. The two cars schedu1ed for perfor- mance testing and the
unmodified GTO were all equipped with 360-hp, 400- cubic-inch V-8s with
Ram-Air kits. We purposely left them outside and under- neath trees during
rainy spells, to find out how much garbage we’d collect through the
functional air scoops in the hood. Nothing – not even a twig – managed
to find its way through the rather small hood openings. A paper element
air filter would have stopped junk from getting into the engine, but would
clog in the process. The Ram- Air kit includes the functional air scoops,
a pan which fits around the carb opening and is sealed to the hood with a
foam rubber lip, and a cam with longer duration intake and exhaust lifts.
The valve springs on Ram-Air engines are much stronger than on the regular
360- hp engine. Triple carburetion is no longer avail- able for GTO’s
but the single Quadra- jet-carbureted engine of 360 hp, while maybe not as
strong a status symbol, is the equivalent or better in performance.
Ram-Air is available only with this largest-of-all powerplants. You’ll
be glad to know that parts from the new 400-cubic-inch engine will bolt
onto the old 389-cubic-inch engines, so ’67 heads will probably find
themselves on many 389 blocks. They have larger valves, relocated valve po-
sitioning, improved combustion cham- bers and larger ports. The new free-
flowing intake manifold will fit earlier engines, but more likely,
there’ll be a lot of last year’s 3-2 manifolds going on ’67 engines.
Cast-iron exhaust mani- folds with individual runners are a feature of the
’67 engine and will ade-. quately serve those who do not wish to install
custom tubular steel headers. Almost as soon as GTO buyers leave any
dealership, they start improving their cars. A surprising number of street
driven ”Tigers” have been modified to make them competitive at weekend
drag events as well as suitable for daily trans- portation. We felt if we
tested a pair of ”fresh” cars, performance would prob- ably be below
this abnormal average. This reasoning prompted our requesting Milt
Shornack to outfit the test cars to this dual-purpose standard. One of his
first steps was to install Royal’s own ”Bobcat Kit.” The kit is
basically a tune-up package and in-
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cludes
thinner head gaskets to raise compression closer to the allowed (and
advertised) 10.75: 1 ratio. Also includ- ed are heat-riser blocked intake-mani-
fold gaskets, lock nuts for the rocker arms which allow the hydraulic
lifters to be adjusted full height, .050-inch larger primary jets for the
carburetor, and instructions on how to get the vac- uum-controlled
secondaries to open quicker. Rounding out the kit is a com- plete ignition
set which contains lighter springs and weights – with positive stop to
guard against too much advance – and a full set of tailored spark plugs.
This kit is easily installed and sells for about $70. It’s available for
all GTOs and can shorten quarter-mile times by as much as a half-second.
Technically, the installation voids the drive train warranty, but then, so
does Sunday drag racing. Pontiac, however, tends to be rather liberal in
its policies because it knows what sells GTOs. Both cars were also fitted
with Hurst, individual-port, equal-length, exhaust headers. These were the
first two sets produced by Hurst and they worked beautifully. Hurst is
just now entering the header business and will offer them to fit all
popular performance cars. Suspensions were not touched in any way, and the
highly-tuned engines were quite docile at all highway speeds, con- vincing
us that alterations such as these don’t affect work-a-day utility of a
prep- ped car. The running gear, except for the transmission, was
identical with 3.90: 1 limited-slip differentials housed in the
heavy-duty, extra-cost, rear-end assembly. Each car had front disc brakes,
and hood-mounted tachometers. Using Motor City Dragway we made a few
passes with the exhaust system closed up and street tires on the rear. The
good elapsed times and high speeds were an indication of better things to
come, but before we did any changing around for quarter-mile running, we
ran our brake tests. We first ran the cars with front-disc brakes and were
fairly happy with the results. But when we brought the drum- braked car to
a halt from 60 mph, we weren’t quite sure what happened. It stopped like
a glue-papered Ay, some 15 feet faster than the disc-brake ver- sions.
This had never happened to us before and needed explaining. Finally we
remembered that while installing the headers, the brake-pressure equal-
izer had to be moved rearward on the frame to clear the new plumbing. Ap-
parently, we didn’t bleed all the air out afterward, or else during
relocation we may have disturbed the balance in the equalizer system. The
front discs locked up much sooner than normal. There was no time to check
the system out, nor was there another car with disc brakes available for
testing, but we do feel that the stock disc set-up will stop in at least
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