Originally Posted by Jake S

its not the chassis that matters. the 4.1 rear towers have more clearance for the battery strap. in a 4.1 it will fit much easier than an old "4" tower.

this was a rolling change because lipos are alittle taller than nimhs that the b4/t4 was designed for.

that being said, YES the gens will fit in the b4.1 chassis. in a t4, generally you dont run your battery all the way back (atleast 1 spacer in the rear)
but if you meant on a b4, yes it is tight, untill you change to a b4.1 rear tower.