I ran a 68 RR 3520#'s 727 TF Turbo-Action transbrake with OE style springs
& CalTracs with a 8-3/4 742 Alum. carrier
worked fine, it was a part time racer really more of a street/strip car,
equates to about 740hp & about 670hp to the rear wheels, that ran in the 9.70's to 9.90's consistently,
same car went 8.58 @ 156 with a 300 shot N2O with same the 8-3/4"
the 8-3/4" are far stronger than given credit for, albeit mine had a trussed housing & aftermarket axles too
even if the Dana-60 {or my Personal Preference is a Strange S-60 even better yet}
either is a better choice for all out drag racing
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Anyway back on topic,
what are your concerns ?,
IMO Probably more in the area of shock adjustment issues,
than type of spring issues
IMO it will hit the tires & work the springs, super-stock springs or not
pretty much just like a manual trans would, just dumping the clutch
Jw has anyone on here used a trans brake with super stock leafs springs