The last few model years of the 2nd Generation marked an odd era for the F-bodies.
When the 2nd Gen was launched in 1970, the midsize cars from Chevy and Pontiac were the Chevelle and the LeMans, both of which were noticeably larger than the compact-derived Camaro and Firebird. A 1970 Pontiac LeMans rode on a 112" wheelbase and was 207" long overall, which is a four inch longer wheelbase and almost a foot more distance between the bumpers than a 1970 Firebird.
If the Firebird in the photo were a 1981 model, it would have been sold on a lot next to mid-size LeMans sedans that had undergone two rounds of downsizing and which rode on a 108" wheelbase the same length as that of the sporty coupe. In fact, the very next year that platform would be re-badged as the Bonneville and would be the new "full-size" Pontiac sedan, and the "mid-size" Pontiac banner would be handed off to an even smaller FWD car. When the 3rd Gen Firebirds launched in 1982, whey whacked a full seven inches off the wheelbase of their predecessor.
It's not that the '79-'81 Firebirds had gotten big and bloated, so much as it is that Detroit shrank around them. It didn't help that a bunch of heavy safety and emissions equipment had been added since 1970, while the motors in the engine compartment shrank in response to the '73 and '79 Oil Crises.
Judging from the wheels and tires and general stance of the car, though, I doubt this thing's rolling with the stock 140bhp 4.3L LS5 V8.
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