Classic/Antique Car Repair: Backfire, air fuel mixture, catalytic converters

Question
I have a 1966 Corvette with solid lifters 327/365

Lately when I start it the car backfires. Scared the crap out of me

Any suggestions on what my problem might be or solution to fix it

Thanks

Answer
Hi Dave:
This is usually a two part solution. First older cars like our tend to run a bit rich all the time, which mean since your car didn't have catalytic converters to re-burn excess fuel, the exhaust system had to perform this job. Back firing was the result if the exhaust system being used to burn excess fuel. Adjust the carbs so she has a better air/fuel mixture. That should fix the problem. A good tune up may be in order.