Wow- so much misinformation, all in one thread...
It's advertised as a 3/4" gain per side, but in actuality you get about 1/2".
And it's not just shackles, you need the offset front spring hangers, too.
And any time your move the hangers, you'll need to move the perches, too.
No wonder your "racers" think the rear end binds...
