Be careful with those Borg and Beck Type 10" Pressure plates and pressure rings if you plan to turn any RPM's..
Ask me how I know...
If you plan to keep it below the ~5200RPM Range your bellhousing, Trans tunnel, and Feet **Should** Be okay.
I have yet to Order one of the Ram Clutches for the 273/slant 6 yet.. They **
should** be skookum as Frig.
Another option to try is the Fiero Diaphgram style Pressure plate with a good 9.25" Chrysler splined 1x23" Disc.
I have Heard about this, But never Have Bought a Fiero Part to try on my own Projects. ( I bought a Spec Clutch from Dion here on the board and I am convinced it is a resprung Fiero Pressure Plate)
- So far so good on that one, as it is installed on my '79 Volare duster with a 225 and an 833 OD transmission.
- → Not all 1"x23 Splined discs have the same pressure angles on them. I found that out the hard way. Ford, Mazda, and Porsche are different from Mopar even though they are all 1"x23 as the pressure angle or spline form as I understand it is slightly different between manufacturers. There is no data I have found published on this but one of my clutch rebuilders have confirmed this.
if you look here there are some options for the Fiero/GM plates:
The clutch disc from the Pontiac / GM Parts will not interchange but the Pressure plate is what we are after here. You may have to mix and match some parts. and whilst doing all this you need the shim the bolted on Bellhousing pivot point about 3/8" - 1/2" closer to the flywheel to make up for the diaphragm plate being "less tall on the the flywheel compared to a Borg & Beck 3-finger design.
The diaphragm style pressure plate will stress your 1960-1966 sissy thin A Body Z bar a lot less, as they do like to break as mentioned in the previous posts.
I Have had Factory Z bars fail on my '62 Valiant, '64 Dart and, '79 Volare. I have repaired and reinforced all of them to not sucking status by reinforcing the Z bar tubing as needed.
Good Luck.