RX7Club.com - Mazda RX7 Forum

Currently working a 90 GTU S5 TII swap less 500 mi on the swap. Still running N/A harness. Having spark problems started with no trailing spark, driving home one night lost tach signal to the cluster misfiring and way down on power. the car ran ok for about a week before I started having these problems. so I had some extra parts laying around from my previous engine and some junkyard excursions. First move was to try a different trailing coil(known good unit) that didn't fix anything. Went back for round 2 about a week later tried a different Crank Angle Sensor(known good unit) same results as round1. now about a month has passed I go back I now have trailing spark but am missing leading spark. tried switching PCM to an N351 N/A PCM no improvement. I am Auto Tech by trade so I feel like I should know this, and I know just winging parts at the thing isn't the proper way to diagnose this but hey I figured it was the easiest way to get an answer. Any advice on how to chase this problem or possible suspects would be incredible.