hi i building a 1964 impala ss that was a late 60s race car, so i have decided to go with that, but i am looking for a bolt on ladder bar system that will fit the impala, is anyone making this or knows something that will work? thanks
Two problems come to mind. First your Impala has coil springs so it moves side to side as it goes up and down causing the ladder bar to bind at it's pivot point. Second issue is a ladder bar even when used with leaf springs that do not move side to side will bind up if you run over a bump with one wheel, or it drops in a pot hole. You already have a three link (or possibly a four link if you have a high performance car) which is the optimal means of mounting your rear axle.
The only thing that separates your factory four link from the one found under a Pro Stock race car is the race car four link is mounted solid with no bushings; only steel bearings (yours is mounted in soft spongy rubber), and your factory stock four link is fixed in it's mounting point (under a Pro Stock race car each mounting point has fourteen possible mounting points, instead of just one. That is how they adjust the car to each of the sixteen tracks they race upon).
I strongly recommend forgetting the ladder bar idea altogether. But if you want to build a trailer queen for show you can find old ladder bars on e-Bay occasionally designed to fit Chevelle that clamp onto the axle and are pinned to the frame with a welded on bracket that you could fabricate easily enough.
The problem with ladder bars is they add another point of rotation that the rear axle must be able to swing around or the suspension binds up as the ladder bar or the stock suspension gets in a bind (compressing or placing the suspension members in tension). To make a ladder bar work you have to remove the stock suspension members. This is what GM did on their GMC pick-up trucks and that NASCAR uses on all of their race cars. Hot Rod's From Hell sells a truck arm conversion kit for your car if you are serious about it.
A ladder bar set up (note it is not stock and there are no stock parts still attached)