Chapter Eight: The Battle of Starcourt - S3-E8
Stupidity: SPOILERS AHEAD: It has been a good minute between Hopper killing Grigory and Joyce turning the key. He could have used that time to run as quickly as he can towards her, instead of staring at her for 30 seconds. Also, Dustin didn't have to yell (through the radio) so panicky yet about closing the gate. While Mind Flayer was killing Billy, El and other kids could have used the time to run further again and get another 2-3 minutes, in that time Hopper would surely come to a safe place.
Answer: They're both muscle cars, but that's about the extent of the similarities. But the 70's were filled with a lot of muscle cars, so some car models may look a bit like another's. Billy's car is a late 70's Chevy Camaro (probably a ‘79). Mad Max's car is a 1973 Ford Falcon XB GT. Incidentally, the Ford Falcon was produced by Ford Australia and wasn't an American car, or even sold in America (as in not sold at dealerships).
Bishop73
According to the experts its a Camaro '78 with added vented side fenders.