Naturally aspirated racing cams to suit engines with high compression (12:1+), ported cylinder head with big valves and well designed intake (45mm+ ITBs) and exhaust system. More top end power than the 'C' cam, pulling to around 10k+ rpm depending on engine. Great for very lightweight chassis for circuit racing with close ratio gearbox. Also suits All Motor drag racing cars. Kelford Cams recommend KVS109-3S valve spring.