rear control arms

[BC409]

hi,guys! lately ive seen some great under car photos that other members have been posting.very nice cars. several have added the left upper arm it seems. my question is this.what about boxing the lower arms? we always did this on later chevelles and it seems like it would be a good idea here too.is it uneccessary or not recommended on the 58-64 cars? thanx bc

[CDNpontiac409guy]

BC... A Chevelle needs that because by comparison, their control arms are made of tin foil :eek: :dunno .
Not sure why, but seriously.... You can literally squeeze the sides of them with your hand.

[gearhead409]

the rear control arms upper and lower twist as the axle moves thru it's full travel. i have been boxing the lower ones on drag race cars but remember, all of the twist will be in the bushings. with hard poly grafite bushings, it makes a very stiff suspension. not real good for a street car.

[jim_ss409]

I boxed my rear lower control arms because I was installing a sway bar and I didn't like the clamp on brackets. I think they are plenty rigid without boxing but I did box the upper control arm, "banana bar" because I thought it might flex a bit. If I had installed a second arm I wouldn't have bothered. At the time I was thinking that I'd be going with a stock stroke 409 and using the car mostly as a cruiser. There must be a fair bit of pull on the upper control arm. At some time before I got my car the bracket that secures the front end of the banana bar to the frame had been ripped out. I'll attach a picture. It doesn't show too well but it was ripped wide open across the top and along one side. If you look closely you can see where they used a bolt as filler when they were welding it up. I had to grind this all out and re-enforce it with an extra plate. Then I welded in a bracket on an angle to tie the area to the frame. This must have been a weak point on these frames because by 64 the factory was installing an angle bracket. I think adding the second arm would take alot of strain off of this area. For those that may not know, Aubrey has brackets that you weld to the rear end so that you can install the extra upper arm. Look under "Our products for 409 cars"
http://www.bruneauperformance.ca/intro.html I noticed that Air Ride Technologies makes a kit for our cars that has new tubular control arms. The upper arm is straight not curved like the factory "banana bar" This seems to be a stronger and easier way to build it. If a straight upper arm would work fine it makes you wonder why the factory would use a curved bar. :dunno
http://www.ridetech.com/productinfo/58-64chevy.asp

[gearhead409]

that's about as ugly as i have ever seen. this is a common problem with the v8 standard shift cars and 40 years of abuse.

[jim_ss409]

It looks like when the upper arm let go the tire came back and crumpled the floor of the trunk. It also pulled the driveline out of the tranny and centre support and let it whip around in there. :( It looked like a grenade had gone off in the tunnel portion of the frame. :eek: I don't want to worry anybody (this car had a hard life) but if that upper arm lets go it can do plenty of damage. Fixing the trunk was the hardest part.

[dq409]

When I installed the poly-g bushings I boxed all four arms.

Still get a firm but not harsh ride,,,dq

[Gus68]

Hey Guys!!! I have a 68 chevelle and a 62 Bel Air, the controll arms on the 62 actually look weaker than the chevelles! Either way I boxed all of the control arms and added poly bushings on both the chevelle and the Bel Air, I also added the fourth upper link to the ol Bel and am in the process of installing a Ford 9". It seems to me that the fourth upper arm needs to be notched to clear the 9" housing if the suspension ever compresses alot. Has anyone
ever had to do this??

[gearhead409]

yes it's very close.i have not had to notch one yet, but i have noticed back in the SUPER STOCK days they were notching them. but as we have all noticed they ran those cars very low at the back axle back then.

[fatride]

I have a 9" rear in my 60 Impala. I rearched my added upper control arm. This is a picture of the cutout I made. Arm was boxed and 1/8" plate was migged to the sides for added strength. Second picture is the stock control arm showing how close it was to the 9" housing.

[gearhead409]

i see you are using ford's big tube hsg. that would make for a tight fit.

[fatride]

Yep, 86 Bronco rear. I also have all the control arms boxed with 1/8" steel and Poly bushings. Nice tight suspension, handles and rides very well. Only weak point in my driveline is 1310 U joints! I guess I'll run em untill somethig breaks! Running through the headers I may have close to 400 HP. I know the Ole timers were running in the 11s and 12s with 1310 U joints. Hayden Proffitt said he never broke a U joint and he ran the 1310s :dunno

[gearhead409]

i have always been interested in our engine as we are building one very similar to put in my wife's 51 chevy truck. if it makes any where near 400hp i will be very happy.

[SS425HP]

Yep, 86 Bronco rear. I also have all the control arms boxed with 1/8" steel and Poly bushings. Nice tight suspension, handles and rides very well. Only weak point in my driveline is 1310 U joints! I guess I'll run em untill somethig breaks! Running through the headers I may have close to 400 HP. I know the Ole timers were running in the 11s and 12s with 1310 U joints. Hayden Proffitt said he never broke a U joint and he ran the 1310s :dunno

Yeah, Ray, but Hayden didn't have the tires we have today. We were only allowed 7" cheater slicks. I never broke one, either. But, I'll bet with 10" tires, they, or something else, would be giving up and quick. You can beef up one thing, and something else goes BANG. Trannys and rear ends come to mind.

Fred