Standard car flashers require load of incandescent bulb to operate, which thermally produces the switching time constant - they will not work with LED lamps b/c LEDs simply draw a helluva lot less current. I built one about a year ago for a 33 ford with a chaser turnsignal effect .... if your interested i could give ya the schematic if you know howto DIY electronics stuff ... I think, however, you can buy the replacement std. flasher unit from the company that made the LED array... Just google LED car flasher or something... Think they're like 30 bucks or so.
Phil