Radiated noise minimization in engine block design, including use of a die - cast aluminum bedplate instead of separate caps. (greencarcongress.com)
The M5 engine is made of aluminum, with bedplate construction for the lower portion of the cylinder block. (bmwusanews.com)
This impressively low weight is down to extensive use of magnesium alloy composite - the block and cylinder head are made of the magical stuff, as is the engine bedplate that sits below the block and adds additional strength to the whole structure. (evo.co.uk)