Benefits to boxing rear control arms

[turbo78]

well, making do with what you got is how 99%of us are. i figure if i cant buy it, i should just build it and make it work. boxing lowers is simple, and it will definately help, boxing the uppers works too as long as you leave a soft bushing in one end. gotta have some give somewhere. 😀

 

[pontiacgp]

in our circle track car we had to run stock rear control arms so we boxed them and used polyurethane bushings on both ends top and bottom with no issues. The back end on a metric moves way too much heading around corners even with the polyurethane bushings...on a 3/8 mile track a boxed rear end isn't too bad but on a 1/2 mile track just that little extra speed down the straight you loose your line turning left....

 

[turbo78]

in our circle track car we had to run stock rear control arms so we boxed them and used polyurethane bushings on both ends top and bottom with no issues. The back end on a metric moves way too much heading around corners even with the polyurethane bushings...on a 3/8 mile track a boxed rear end isn't too bad but on a 1/2 mile track just that little extra speed down the straight you loose your line turning left....

well, guess it's a good thing he aint runnin around in circles in the dirt then huh? asphault and dirt... 2 totally different surfaces.

 

[pontiacgp]

turbo....did I mention a dirt track?...

 

[Carsten]

Could the original control arms be a reason for the car beginning to "shake up" on speeds over 100 miles per hour on full throttle ? It behaves like if air pressure is much to low on all 4 tires !? Car has nearly 300 hp at the wheels , 350 engine and th350..
Greets , Carsten

 

[pontiacgp]

have you checked to see if drive shaft is out of balance?

 

[turbo78]

have you checked to see if drive shaft is out of balance?

i 100% agree with you on the driveshaft, i experienced that myself and i also had a rear rim that wasn't good and straight. but i wouldnt feel anything until speeds over about 70mph and then the whole car would act like it was in a severe crosswind swaying back and forth while excellerating. 😀

 

[Bonnewagon]

Carsten, are you talking about 100 mph on the Autobahn? I used to ride a BSA 650 Lightning over there in the Army and I recall that your roads were smooth as anyone could want. I used to cruise at 90-100 mph and that bike felt like a giant vibrator. So if you're getting vibrations look to all the rotating mass like wheels, tires, driveshaft, axles for proper balance. I know they don't allow rustbuckets on the road over there so I'm assuming your car is sound. Totally shot bushings would allow the suspension to be sloppy but the arms themselves wouldn't cause trouble, unless they are rusted out.

 

[pontiacgp]

that bike felt like a giant vibrator

you just probably made the best motorcycle add to encourage the ladies to buy bikes... :lol:

 

[Bonnewagon]

As soon as I posted that I knew someone would pick up on that! I should have added "not that I would know how that feels!!!".