why swap the 8 for the 9"?

are you racing? putting serious torque to the ground?

trans brake with a big stall?

the 8" is more than strong enough for pretty much whatever you want to do with it.

we have a maverick with a strong 302 that runs 10.12 in the quarter with the stocke 8" axle, and 4.56 gearing.

to me theres no reason to swap the axle, unless of something like your axle is broken, andyou just happen to have a 9" laying around..?