This mounts to your block and allows use of the original mounting plate. Needed for any 5 series block, late e24 and most 7 series. These motors are missing the two aft mounting lugs on the block. My pic shows an 88 635CSi with lugs and mount on the block so it is not needed, this adapter mounts behind this if it is needed. New they are $95, this one is $75 including shipping.
