Flywheel Q's

[wetoolowdingbangow]

Im trying to find the right flywheel for me application but im failing so far. I have a 12 inch luk clutch for my sm465 and im only finding flywheels for 11 inch clutches.

Dumb question but will the flywheels for 11" work for my 12 inch clutch?

Ive checked rockauto and they have a cast iron one, which is ok but I hear bad things about cast. im not doing any 9 second quarter miles obviously lol so maybe the iron one is fine?

Theres also the autozone route....im sure thats cast as well.

I looked at summit and they have several high dollar ones. The steel one I like is for an 11".


Any ideas or experience?

 

[4X4HIGH]

Most flywheels that use an 11" clutch will accept the 12" disc as well. Just need to make sure that the bolt diameter for the 12" pressure plate is on the flywheel (most flywheels have dual patterns). Also most factory flywheels are cast iron.

 

[diesel4me]

I bolted a 12" pressure plate right to a flywheel that had an 11" clutch factory,back when I converted my '72 K5 to a SM465 from a TH350..

The bolt pattern was the same--I used a flywheel from a totaled '72 K5 just like mine,along with the trans,transfer case and driveshafts..

I found out the 12" clutches are not really much better than an 11"..the surface area isn't all that much larger,and the hassles you may encounter with bell housing clearance and the 3 fingered style pressure plates failing twice I had installed in short order, was what convinced me to stay with an 11" clutch..
The cast iron "open bottom" bell housing I used cleared the 12" clutch fine,but if you try using the later "car" style aluminum ones,there may not be enough clearance for a 12"..