Trans Am Of The Week

The 1974 Pontiac Trans Am

The 1974 Pontiac Firebird Trans Am had a new front and rear end treatment due to new bumper standards required by the government .So 

Curb weights rose dramatically in the 1974 model year due to the implementation of 5 mph (8.0 km/h) telescoping bumpers and various other crash and safety related structural enhancements; SD455 Trans Ams weighed in at 3,850 lb (1,750 kg) in their first year of production (1974 model year; actually 1973).

The 1974 models featured a beautiful redesigned “shovel-nose” front end and new wide “slotted” tail lights which looked very good. The engine choices In 1974, were two base engines for the Firebird: a 100 hp (75 kW) 250 cu in (4.1 L) inline-6 and a 155 hp (116 kW) 350 cu in (5.7 L) V8. Available were 175 to 225 hp (130 to 168 kW) 400 cu in (6.6 L) V8 engines, as well as the 455 cu in (7.5 L) produced 215 or 250 hp (160 or 186 kW), while the SD-455 produced 290 hp (220 kW). The 400, 455, and SD-455 engines were offered in the Trans Am and Formula models during 1974.

The Bill Mitchell 1974 Chicago Auto Show Car.. Bill Mitchell was the 
Head of design at General Motors 1958-1977. And he 
wanted a prototype for the 1974 car show circuit, so the design team, headed by John Schinella, started back to work on the 1973 TA. Although the gold leaf bird and the black-and-gold paint scheme stayed the same they added molded fender spats instead of the bolt on ones used on the previous TA’s, hoping they would make it into production.

But they never did enter production (cost reasons). The 455 SD replaced the 455 engine with solenoids under the shaker that would  open the round butterfly nostrils of the rear facing hood scoop when the driver romped on the gas pedal. (1973 Was the first year the Shaker was non functional) The 1973 bumper was replaced with the 1974 shoveled look front bumper and rubber padding for the new safety regulations. General Motors Design badges were added to the front lower fenders along with the German Gothic lettering depicting the new Trans Am decal in true gold leaf. The Cibie headlights were integrated into the design.

The special silk material used on the seats and the Cadillac carpet with the stainless steel floor grates that protected the carpet from wearing out (John Schinella used these grates on his other concept cars) were part of the one-off interior. The first gold dash bezel was used on this 1974 Trans Am as well as on all Limited Editions  and later Special Editions . Special tires made by Goodyear with gold lettering were mounted on the first gold honeycomb wheels with the geodesic design by Bill Porter (not first honeycomb rims but first ones that were done in gold). What they came up with was a huge success on the promo show circuit.

The SD 455.

In 1973 and 1974, a special version of the 455, called the Super Duty 455 (SD-455), was offered. The SD-455 consisted of a strengthened cylinder block that included four-bolt main bearings and added material in various locations for improved strength. Original plans called for a forged crankshaft, although actual production SD455s received nodular iron crankshafts with minor enhancements. Forged rods and forged aluminum pistons were specified, as were unique high-flow cylinder heads.

The engine added $521 to the base price for a Trans Am and $675 for a Formula. A four-speed manual transmission was standard, and the rugged Turbo 400 three-speed automatic was optional. Air conditioning was available with the automatic transmission, but that pushed the rear axle ratio up to 3.08. Non-A/C cars received a shorter 3.42 Set of gears

There was a lot of confusion about the horsepower rating. A lot of the car magazines at the time were promising 310 horses. Its power was achieved through bending of EPA emissions-testing procedures, which led engineers to de-tune the engine to 290 hp due to a camshaft change to the same profile used in the early RA III 400 engines for mid-1973 and 1974 Nevertheless, when the SD-455 finally hit the street, praise for it was universal, especially when it turned mid- and high-13-second e.t.’s at a time when a new big-block 454 Corvette was a second slower. 

Interior..

Notice the 8 Grand Tach and the 160 MPH Speedo I’m sure with the right gearing and proper tuning to a SD 455 car that 160 might actually happen..

 This has got to be one of my most favorite year of Trans Am besides my own.. The last year of the regular rear window and true dual exhausts.. 1975 would bring in the dreaded catalytic converter    but the very awesome HEI Ignition that did away with those annoying points you had to tinker with every so often was introduced 

As much as I love the 70 to 73 Front end styling, the 74-75 shovel nose is another favorite of mine. I wanna say 1974 was the last true year for the bad ass Trans Ams.. Even one version of the 400 still put out 225 Horse, an intake and cam with some carb adjustments would change that real quick ! In 1975 Power dropped immensely the 400 would be rated at 185 HP and they would introduce the 455 later in the year calling it the 455 HO and giving it 200 HP yes it was just a station wagon motor choked by emissions.