With a few extra options, a big block Nova or Camaro could actually weigh more than a similar Chevelle with base equipment. The L78s were and still are touted as killer as well. I've had two and even with headers and tuning would be hard pressed to get into the 12s. They can perform but do need help. From my experience the L72 probably did feel brutal compared to the L78. Years ago magazine writers took manufacturers' hype and ran with it. Still fun cars to drive though. The older they get the faster they were.
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Chevelleless after 46 years......but we did find a low mileage, six speed, silver 2005 Corvette. It will just have to do for now.