how much height are you getting from doing a add a leaf?
what is the difference between a short and a long?

i did torsion keys and shackles. and because i had to crank the keys to get my tires to work my front sits a bit higher than the back (1/2 inch)

has anyone done add a leaf and shackles? (any pics of how it sits)

 

I'm new to Blazers but isn't the rear an 'axle over' ( SUA) wouldn't adding a leaf lower you down?

 

a block will lower it, however i believe a add a leaf will get rid of any sag and lift a little

 

yah...Search Pro Comp ADD-A-LEAF...there should be a thread that pops up when i added mine. I got about and 1.5" from mine.

 

adding a leaf will make the whole spring pack stiffer. Spring rates are measured in lbs/in. ie a stiffer spring will compress less for a given weight.

Back to the question. a longer leaf will raise the rear end more but also make the ride stiffer. a shorter leaf will not raise it as much. The grease guy at my work had an extra leaf put in on each side at the local spring shop and it raised the back end higher than could be compensated for in the front. That said he doesn't have torsion bar keys they just cranked up his bars as much as they felt comfortable doing.
hope that helps.