The DFV design used a similar cylinder head to the one on the FVA engine wih custom cylinder block and crankcase . This created the legendary DFV - literally meaning `` Double Four Valve '' . The DFV design used a similar cylinder head to the one Duckworth had prototyped on the four-cylinder FVA units on a custom Cosworth cylinder block and crankcase , forming a single 90 Â V8 engine , thus creating a legend in its own right , the DFV - literally meaning `` Double Four Valve '' .