The year nineteen-seventy-two was the year when the Trans Am began to feel the pinch of the new horsepower ratings. All horsepower now was rated as SAE net , where the engine's hp numbers reflected the as installed configuration. This meant the engine's output was measured with the alternator, water pump, fan, exhaust system, etc., all installed. The grossfigures which had been cited in year's past, were reduced by approximately 15%.
As a result, 10 net horsepower was lost with the ratings dropping to 300@4000 rpm. The torque figure actually went up to 415 lb/ft @ 3200, a net increase of 5 lb/ft over the 1971 version of the engine.new posting of 415 lb/ft @ 3200 rpm. The engine was still tagged as the 455 H.O. on the outside, but much changed on beneath the valve covers.
A new cylinder head rested atop the 4-bolt block, this had a new casting number of 7F6 and was only used in 1972 and had special combustion chambers. The good part about these new heads is that they still used the horsepower producing oval ports and the accompanying large 2.11" intake and 1.77" inch exhaust valves found in big inch Pontiac high performance engines of the past. The 068 camshaft was back for another run in the TA, and the lift reamined at .408/.406 inches for intake and exhaust. Transistorized ignition supplied the spark on all 455 H.O. engines.
As in 1971, there was only one engine available in the Trans Am and it was subject to same hand selection of components in order to make the engines as close to the tolerances laid out in the blueprints. This engine could be mated to a pair of transmissions, the infamous "M22 Rock Crusher" Muncie 4-speed close ratio manual transmission or the sturdy 3-speed TurboHydramatic 400 automatic transmission. When ordered with the manual, the engine was coded WM, or WD. If the automatic was chosen, YB or YE was stamped into the block
Three rear axle ratios were available for the 1972 Trans Am. When equipped with a manual transmissioned or an automatic without air conditioning, a 3.42 gear was supplied. If your automatic had air conditioning, a 3.08 rear axle would be substituted. Should you chose to do without air conditioning and were willing to shift yourself, the 3.73 rear axle could be checked off on the order blank. Cooling concerns during high ambient temperatures was one of the reasons cited as to why optional equipment dictated gear ratio choices.
The infamous shaker hood scoop would also let in it's last gasp of air through the rearward facing inlet. The new noise standards coming in 1973 would no longer let this useful secondary source of air survive. From '73 onward, the shaker would still shake, but would be forever sealed. Underneath the shaker was a big Rochester Quadrajet 4-bbl carburetor that sat atop a cast aluminum intake manifold. Like the functioning shaker, the cast aluminum intake would disappear from the Trans Am's list of features.
All Firebird's benefitted from a new grille for '72, taking on a fine elonagated honeycomb appearance (perhaps to match the wheels?). The colors once again remined limited to Cameo White with blue stripes or Lucerne Blue topped with a white stripe. Lucerne Blue would have it's swan song in 1972 as a blue would not return to the Trans Am line up until 1974. The "racing' stripes that were first intoduced in '69 also made their last appearance in 1972 and no Trans Am would be striped as such until the 15th anniversary T/A in 1984.
Interiors were given a new look with new "morokide" vinyl being available in either standard of custom trims. The Potomic cloth and vinyl morokide combination was available, but as in the cloth/vinyl trim of previous years, it was limited to black or beige. The seat cover styles between the standard and custom interiors was the horizontal pleats had a nice finished border about them.
Pricing of the Trans Am actually dropped in 1972, being priced less than the $4305.00 of the 1970 introductory base. The '72 carried a base price of $4256.00.
Due to a 1972 UAW strike, at which GM was the target, Firebird and Trans Am production was devastated. All told only only 1286 Trans Ams were completed (at the plant, over 2,100 Firebird and Camaro models were in various stages of assembly when the strike ended, but as these cars would not meet the new 1973 Federal standards, these cars were all scrapped !) with an untold number left on the line that would never make it to final assembly. Automatics out numbered the 4-speed cars by nearly two-to-one with and 828 to 458 margin. The 1972 Trans Am production would hold the distinction of being the second lowest in history.
Engine |
Transmission |
Production |
Total Production |
455 H.0. |
4M |
458 |
455 H.O. |
3A |
828 |
|
|
|
1,286
|
Exterior Colors |
Code |
|
Interior Colors |
Std Trim |
Code |
Custom Trim |
Code |
Cameo White |
11
|
|
Blue |
Morokide |
|
Morokide |
211 |
Lucerne Blue |
26
|
|
Ivory |
Morokide |
121 |
Morokide |
221 |
|
|
|
Saddle |
Morokide |
131 |
Morokide |
231 |
|
|
|
Green |
Morokide |
141 |
Morokide |
241 |
|
|
|
Beige |
|
|
Morokide |
251 |
|
|
|
|
|
|
Cloth & Morokide |
351 |
|
|
|
Black |
Morokide |
161 |
Morokide |
261 |
|
|
|
|
|
|
Cloth & Morokide |
361 |
CID |
Trans |
Code |
RPO |
HP @ RPM |
Torque Lb/Ft @ RPM |
455 H.O. |
3-Auto |
YB, YE |
LS5 |
300@4000 |
415@3200 |
455 H.O. |
4-Manual |
WD, WM |
LS5 |
300@4000 |
415@3200 |
Transmissions
RPO |
Speeds |
Code |
Usage |
M22 |
4-Manual, Close Ratio |
WJ |
Opt |
M40 |
3-Auto |
PQ |
Opt |
Rear Axle Availability
Engine |
Trans |
Axle Ratio |
Axle Code |
Restrictions |
455 H.0. |
3-Auto |
3.08 |
GYG |
Req w/Air Cond |
455 H.O. |
3-Auto |
3.42 |
CJG |
Std. w/o Air Cond |
455 H.O. |
4-Man |
3.42 |
CGG |
Std. |
|