Have you seen this video? https://www.youtube.com/watch?v=1_ptUrQOMPs
Both cars were destroyed, but the occupants of the new Impala would have suffered minor injuries. The driver of the old Bel Air was dead on impact.
The good news is that in a serious accident, your cars would probably utterly demolish a modern car and your cars would probably be repairable. The bad news, is that you would probably be dead as the driver. This is not comforting. Mass != safety.
I’m not certain, but one of those may be a pre-1970 model. If so, there are no steel beams in the doors. That means, there are two sheets of steel a little thicker than the metal of your refrigerator door between you and a “t-bone” type accident. Those are usually crippling or fatal in pre-1970 cars above 30 miles an hour.