I just don't understand why people think they need to adapt a rear into AMCs. Sell all that slo-par stuff and buy a set of one piece axles for the AMC-20. Also there are at least a dozen great posi units available if you don't have a Twin-Grip. If you plan on running slicks I'd reinforce the spring perches & weld the axle tubes to the center section (I'd do this on ANY rear, any car). I did this to my 70 AMX rear back in 1972 plus I used an AMC 4.44 gear set and 1 extra clutch spacer in the Twin-Grip (it is a 390 left hand thread model). Despite many 6000 rpm launches w/4sp and 9" slicks the only thing replaced to date is a wheel bearing and lube changes. When my car goes in the 10's i'll change to a Dana 60 ! BTW, There is a nice aluminum rear cover w/cap braces available now (LPW if I remember) and I hear someone is making a spool for racing also. Because the 20 is used in Jeeps !
the H-D parts just keep on coming !!!
The post about 8.75s being used in dragsters was true back when they spun the tires the whole quarter mile, as soon as the tire tech caught up to the horsepower they changed to stronger rears. (spinning tires don't break rears traction does).
I hope this info helps.
amxron
70 AMX E/S NHRA/IHRA
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