I installed a 123 distrbutor on a 1971 Mercedes 280 SL and have set the timing with a light. The car starts well and idles well. I get some backfire on acceleration from a dead start but it isn't always there and after running it today for an hour or so, was getting some backfire at running speeds around 3000 rpm. The car has new plug wires from about one year ago with little run time on them and standard Bosch plugs. I'm wondering if I need new plug wires and a different type of plug. I replaced the coil with a high performance Bosch coil. The curve was set on the "E" setting upon installation. Any thoughts, help appreciated.
