Belated modern update on the C12, with better chassis and unit construction engine. Okay for mild use but exploding gearbox, poor valvegear materials, weak big-end and nasty clutch turned up when they were thrashed. The later models were much improved. SS80 was tuned with roller big-ends but could still blow up the gearbox and was generally short-lived. Best buys are late C15’s with upgraded electrics.