more volts is not the answer.
The power of an electromagnet is determined by the wire size and number of windings in it.
The larger the wire size, the more amps you can apply.
The more windings, the more electromagnet force.
This rule applies from the smallest relay coil up the the CERN SuperCollider.

( The above is a gross oversimplification, but I think you get the gist )

Bottom line : You ain't gonna make the OEM SC clutch grab any harder by increasing volts or amps, it's doing all it can do with 14v and whatever amps it is drawing without blowing the fuse.
You would need what was called back in the good old slot car racing days, a 'rewind'.

Has anyone looked to see if the clutch on the V8's are any stronger and will the M113 clutch fit on the M112 SC ?