Cutting GM control arms

[92ShoOff]

I did some searching and didn't really find an exact answer to the question I have in mind, so here it is: Is there any way to know if you need to cut these control arms, and how much exactly you'll need to cut BEFORE taking the car to have it all aligned???

I'm still wrapping up the Tokico/Intrax install and I don't want to cut the control arms too short and end up needing to buy another set.... nor do I want to get this stuff all together just to get it to the shop and end up having to bring it back home and tear the control arms back off again to cut them down. Cutting the new control arms the same length as the old ones would be ideal if I wasn't lowering the car. I'm not even sure as it is if the new arms can be adjusted down to that same length without any cutting.

What if I were to cut these new arms to where they at their furthest point they reach the same length as the older ones? That would then allow them to be adjusted shorter if need be and that should be enough to get my rear end in alignment, correct? Since I'm lowering the car the new arms shouldn't need to stretch out any further at all than the length of the old ones I assume.

How would you guys recommend cutting these arms if I need to cut them.... should I use a hack-saw, or a reciprocating saw? Or is it best to maybe start the cut with a hack-saw and finish it with the reciprocating saw??

Anything else I might need to get the correct alignment for the rear end with this setup (ie: camber plates), or should it all be able to be aligned to the factory specs since I'm using Intrax springs and the GM control arms??

Thanks for any help you guys can give. I really don't know a whole lot about alignment and lowering so almost any advice would help me greatly. Thanks!

-Andrew

 

[Shoaz]

As long as they're cut such that you have some adjustment range you won't need camber plates. One of the big advantages of the GM arms is that they're adjustable, so that's all you need to adjust camber and toe in the rear to whatever you want.

 

[jelloslug]

I had to cut .25 of an inch off of each threaded end to get enough room to be able adjust it to spec.

 

[92ShoOff]

So how exactly did you figure you needed to take 1/4" off all 8 pieces (or 1/2" off all 4 arms)?? Did you put it together, take it to a shop and was told you'll need 1/2" off each side? I just don't want to get ahead of myself and cut 1/2" all the way around and end up having screwed something up.

I've heard some people say they haven't had to cut anything, some say 1" all the way around, and others say 1/2". How were these cuts determined??

Thanks guys!

 

[DHMag]

So how exactly did you figure you needed to take 1/4" off all 8 pieces (or 1/2" off all 4 arms)?? Did you put it together, take it to a shop and was told you'll need 1/2" off each side? I just don't want to get ahead of myself and cut 1/2" all the way around and end up having screwed something up.

I've heard some people say they haven't had to cut anything, some say 1" all the way around, and others say 1/2". How were these cuts determined??

Thanks guys!

when i first did mine, i cut 3/8" off each end. with the car lowered 2", the 3/8" trim was not enough. i ran out of adjustment before the tire was cambered properly. when i redid the rear suspension, i cut another 1/4" from each arm. i could actually use about another 1/4" trimmed, but the alignment guy said it was good. so, i cut a total of 5/8" from each end. my guess on this discrepancy is the various part numbers available attribute to the different lengths.

 

[jelloslug]

When I did mine I kept cutting unit I could lay the new arm on the old one and put a bolt through both ends at the same time. Then I cut off a little more so I would have extra adjustment. How much you have to cut depends on if the car is lowered or has bad springs.