A friend ,I helped: 67 Nova post,caged 4:30's in the 12 bolt.327 small journal (big heads,big solid ,bla bla), He borrowed one of these crappy (this actual drive shaft style...) turds... He ran it,(drop the clutch at 3500 - 4000,pull the trigger a 6800-7000...(four speed Muncie..) We did a chalk line on both drive shaft parts,it was rotating during each pass...He had a one piece properly one built,he picked up two tenths... Not even going to mention of possible damage ,to the drive train & and safety....