I ' am going to build my own rear control arms on my 79 elky but was woundering should I use round or square tubing what do you all think I should use? LMK :P

In general, bends (read square) increase strength.

Why don't you just box in the stock ones? I welded 1/8 steel plates to the bottom of mine. I also welded peices of 1/2 tubeing to the inside to reinforce the sway bar holes. I then installed poly bushings in the arms. There made a big difference in the feel of the truck, better handling & reduced wheel hop.

well it would be the fastist why but I have all the time and equipment to do it why not? I'll consider it if pepole would look under the car they would no be wise to the mods and consider racing

Do people often look under you truck before they agree to race you? :?

Chrome Molly tubing is pretty strong and lightweight. However I haven't heard of anyone braking the stock controll arms while racing, that doesn't mean it never happened. Flex is, my understanding anyway, what you want to get rid of without changing the Pinion angle. Boxing is a great inexpensive way to do that.

Now you could do the Chrome Molly tubing and then have them chrome plated but plating would weaken the metal, it would look good underneath, though a little out of place if you didn't detail the whole underside.

I'm just talking. :-)

I bought a set that were made of square tubing, came with poly bushings. Didn't cost much more than getting a set of bushings and having a machine shop press them into the old control arms. The old rubber bushings were getting soft and needed replacement anyway, so the car needed replacement. Might as well put in the good stuff. You can find a couple sources in mags like Chevy High Performance.

I think www.summitracing.com or www.jegs.com have aftermarket control arms for a-bodies. Some of these are adjustable also.