when im driving my car around the block or for a short period, the spark twitches, when im driving for a long period and doing about 120 km/h. it cuts out. only the car dies. the radio power windows, everything else is fine. I changed the interior over from a 1983 to a 1992, along with the harness. I changed the multi switch, changed the starter switch. im running an hei distributor, with a holley tbi. its a 347 stroker motor. I have no idea what else I can look for. any ideas? thanx