<P> The 1972 models saw the first wave of emissions reduction and safety equipment and updates . GTO was a now sub-series of the LeMans series . The Tempest, was dropped, after being renamed' T - 37' and' GT - 37' for 1971 . The base 1972 mid-sized Pontiac was now called LeMans . </P> <P> James MacDonald left the post of general manager to be replaced by Martin J. Caserio in late 1972 . Caserio was the first manager in over a decade to be more focused on marketing and sales than on performance . </P> <P> For 1973, Pontiac restyled its personal - luxury Grand Prix, mid-sized LeMans and compact Ventura models and introduced the all - new Grand Am as part of the LeMans line . All other models including the big cars and Firebirds received only minor updates . Again, power dropped across all engines as more emissions requirements came into effect . The 1973 Firebird Trans Am's factory applied hood decal, a John Schinella restylized interpretation of the Native American fire bird, took up most of the available space on the hood . Also in 1973, the new Super Duty 455 engine ("Super Duty" harkening back to Pontiac's Racing Engines) was introduced . Although it was originally supposed to be available in GTOs and Firebirds, only a few SD 455 engines made it into Firebird Trans Ams that year . One so equipped was tested by' Car and Driver' magazine, who proclaimed it the last of the fast cars . But the pendulum had swung, and the SD 455 only hung on one more year in the Trans Am . </P> <P> All Federal emissions and safety regulations were required to be in full effect for 1974 causing the demise of two of the three iterations of the big 455 cubic inch engines after this year . The last version of the 455 would hang on for two more years before being discontinued . </P>

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