Question on flywheel differences

[Johnny B]

Hello all,

I have a question regarding the difference in 2 flywheels and don't have both parts in front of me so can't compare the two.

Can a 1986 4.7S flywheel PET part no 928 102 075 01 for an M28.44 engine be used in a later 928 S4 5.0L M28.50 motor with the PET part no 928 102 075 04

I know the part no's are slightly different and obviously so are the engine sizes, however do the flywheels measure & weigh the same and have the same no of teeth?

Any and all help greatly appreciated

[Mrmerlin]

the 86 early flywheel is for a dual disc,
the S4 is single disc.
928 INTL lists two different parts so I would say they are not interchangeable

[Johnny B]

Thanks appreciate the feedback

[Sapientoni]

The number of teeth on the ignition ring are different and will not allow the newer engine/chassis to run at all, for certain if it's an automatic. The later flywheel will not fit the earlier block with the starter mounts being different and no clearance. Maybe a spacer on the crank will allow it to fit, haven't tried that yet, but need to.

[Johnny B]

Originally Posted by Sapientoni

The number of teeth on the ignition ring are different and will not allow the newer engine/chassis to run at all, for certain if it's an automatic. The later flywheel will not fit the earlier block with the starter mounts being different and no clearance. Maybe a spacer on the crank will allow it to fit, haven't tried that yet, but need to.

Thanks really appreciate the information