GM’s RWD future was looking rosy until the U.S. government decided to vote in favor of new CAFE rules, forcing carmakers to improve the average fuel economy of their fleets to 35mpg by 2020. We were teased with all manner of RWD, V8 powered muscle cars, including sedans, coupes, and even a sports wagon but now many of these cars have fallen off the radar.

Some of the cars will still arrive, such as the Pontiac G8 range, Chevrolet Camaro, and possibly a G8 Ute, however, others such as a new RWD Impala and a next-generation Holden Monaro/Pontiac GTO are unlikely to see the light of day anytime soon. “I think (the Monaro/Pontiac GTO) is gone for now,” GM product czar Bob Lutz told GoAuto at the recent Detroit Auto Show. “We’ve got nothing in the product plan right now like that. We’d like to have, but you can’t do everything.”

Lutz revealed that the plans were dropped because of GM’s need to downsize its range in order for it to meet the upcoming CAFE regulations. “In terms of fuel economy, that’s not the end of the market where we want to stimulate demand,” Lutz explained. “We have to find ways to stimulate demand and desirability in cars that will get us closer to the 35 MPG average.

Instead the future lies in the new ‘Alpha’ midsized platform as well as SUVs derived from car platforms rather than a truck-base chassis. However, Lutz was quick to point out that Alpha still hasn’t been given the green light and that officials are first waiting to see how the entire CAFE deal pans out. If given the go ahead, GM will once again call upon its Holden division in Australia to develop the new Alpha range.