In my experience with drag racing The ONLY benefit is a reduction of friction on the guides all but eliminating guide wear. As for performance the only thing it did for my 401 which saw 7000 rpm all the time was let it idle a little smoother. They are for durability and not for performance.
78 pacer on 75 chero frame thats shortened 10\" and shackle reversal, D60 front with spool,14ff with detroit locker 4.56s in both,500 hp/500 ftlb torque 401,built 727,208 to divorced 205 doubler,on 46x21 ag tires
78 cj 360, 3spd, scout 44s with detroits SOAed with 36"tsl and beadlocks