Pontiac had tried to re-engineer the Chevrolet Camaro for its own Firebird model, and it did manage to achieve better suspension, relocate the engine and use a stock of its own engines. However, in 1970 when Pontiac launched the second generation Firebird it was much closer to the Camaro. Pontiac was forced to share the new F-body given to the sibling Camaro, with its distinctive extra long door and combined b and c-pillar. Pontiac wrapped its extremities with endura foam moulded to provide 5mph protection and painted in body colour. The 1970 Firebird came in a base model with a choice of six cylinder or V8 engines, and above those the performance 350 and 400 V8 cars. For 1971 a new 455 engine was added, but the body was unchanged and continued without alteration for 1972. Trans Am versions were declining in sales even though they could be optioned with the most powerful 455 engines. However, emissions regulations were tightening and even the most powerful engines had to be restricted more each year. New 5mph bump regulations saw the 1974 Pontiacs given 'shovel nose' fronts. The biggest change for 1975 was a wraparound rear window and revised roofline. For 1977 a new slant-nose front was given with 4 rectangular headlamps differentiating it even more from the Camaro which kept round lamps. A new crosshatch grille appeared for 1978, and a new front end for 1979. Large engines were killed off for 1980, and the second generation Firebird itself flew off in 1981 to be replaced by a new generation car.