SBF clutch question
 

I'm planning on replacing the clutch and pressure plate in my '65 (has lots of "clutch judder"), and am not 100% sure on the right clutch plate for this setup. I'm running a moderately-built 289 (about 300 HP) and a Toploader 4-speed. But....the Toploader was pulled from a '69 Mustang with a 428 CJ and has the large 1 3/8 " input shaft (case id# RUG-AE2). According to the PO who installed the tranny, it's currently running a 10.5" clutch, but all the clutch discs I've seen advertised for the big-block transmission and 1 3/8" input are 11 or 11.5". Before I order the parts, is there any way to know for sure whether I'm running a 10.5 or 11" clutch without actually dropping the tranny? Also...will a 11" disc even work with a small-block bellhousing? Any advice on the best clutch/pressure plate kit for this beast?

You need to drop the trans out and have a look..A short shaft big block trans should not even reach into your pilot bearing in the back of the crank...This is obviously not good for the trans and may even be part of your shuddering problem...There were special pilot bearings that supposedly worked with that combo but anyone that I heard that ran one had problems with them falling out.

Yeah...that's kind of what I thought. I've actually got a weird situation with this combo because the PO also claims to have installed a flywheel off a 390 when he put in the big-block trans. Everyone I've talked to says this is a load of crap because of bolt pattern and balance incompatibility issues. I asked the PO specifically about this, and he said he had the entire rotating assembly "balanced" to work with the 390 flywheel (engine also has a 50 oz harmonic balancer from a 5.0 HO). All I know for SURE (based on the main case housing id#) is that it does indeed have a trans from a '69 428....and it seems to work.