why would this tool be used on a V12 M70 engines?

[Mordan]

Petrol Engine Timing Tool - BMW M40/M43/M70/M73 Sealey VSE118

http://www.justoffbase.co.uk/core/media/media.nl?id=39612&c=317638&h=5140dd9897ed42b338eb
http://www.justoffbase.co.uk/Petrol-Engine-Timing-Tool-BMW-M40-M43-M70-M73-Sealey-VSE118

I learned though that the M73 is used on a Roll Royce :)

Is the M40 similar to the M70?

[shogun]

yes,
Suitable for setting the camshaft in the timed position on BMW M40/M43/M70/M73 petrol engines.
Camshaft alignment tool for BMW M40/M43/M70/M73 petrol engines.
Contents: Camshaft Setting Plate, Locking Pin

For V 12 engines you must have 2 blocks and the locking pin for this procedure

http://www.zdmak.com/wbstore/main.asp?action=PROD&PROD=BMW3035&CTMP=1&LowCt=0

[Jon K]

OP: M70 is SOHC - thats a "cam lock" tool for an SOHC motor.