After listening to all the advice, thanks to all who contributed, I obtained an EU3 cam cover, rover coil packs and HT leads from a fellow caterham owner and converted from EU2 to wasted spark with the EU3 cover and twin coil packs. Distributor, single coil and HT leads removed. EU3 cam cover fitted along with the rover coil packs. An additional coil driver was pinned from the (early) Emerald ECU. The coil packs share a power feed. The Emerald ECU config was changed as per Oily's instructions. Spark plugs where BCPR7ES so haven't been changed. The engine runs well once it has been started, but, it's the starting which is now an issue. Engine turns over and does not fire until the third or fourth attempt, often there is a loud backfire as (I'm guessing) unburnt fuel catches in the exhaust! So what have I done wrong, something to do with with the setup whilst the engine is cranking? As I say the engine runs well once it catches. K series 1.8k. Supersport cams. QED throttle bodies. Emerald ECU (early version). Any/all advice welcomed Thank you Chris