Clutch disc 4-Speed Barracuda 1966

Here is some info taken from Slant6.org concerning pressure plates and clutches. They're referencing the slant but since the V8 used the same size equipment, it looks like it should be applicable for the V8 as well since it too used the same size flywheel, pressure plate and clutch as the slant:

The heavy duty pressure plate and disc for the SL6 is a 10 inch size "cover type" Borg & Beck, 3 lever unit. These units adds some needed surface area while still bolting to the stock 122 tooth flywheel. This is a special cover with it's six mounting bolt tabs which are inset into the cover. Here again, these pressure plates have lots of room for additional and /or stiffer springs but the inset tabs are a weak point where cracks start forming as spring pressures go up. This pressure plate is Borg and Beck # 1576 and be sure to inspect the tab areas closely if you use one. These units mount to the flywheel with special reduced hex size cover bolts.
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It might be advantageous to upgrade to this larger pressure plate and clutch keeping the same bellhousing.