[Impala383]

I ordered s set of 2 inch lowering springs for a 71 Chevrolet impala from spring max. Installed front and rear springs and once i lowered car to ground noticed that rear end angles slightly towards shop floor. I called guys and spring max and they told me that you Can have some negative or positive angle on the rear end. Just wondering if anyone on here would know if that is correct or how i can fix problem with angle of rearend. I reinstalled stock spring absorbers on top of rear springs. Thanks for you help with this.

[matts37chev]

you could use some axle shims to fix it, they come in all kinds of degrees and widths

[nialkc]

Actually about 2 degrees downward pinion angle is no problem, when you get on the throttle your chassis lifts and your angle disappears. I dont recommend upwards angle as it gets worse. Hope this helps Nial

[Impala383]

Thanks i will look into the shims also. If i can't do anything with it. I will just wait and see how drive shaft universals react to it. I am having drive shaft shortened because i installed a 700r4. Appreciate the info on the angle. Thanks for help once again.

[Centerline]

For a street driven car you need to have the pinon angle within about 1 degree of the trans output shaft angle. If your pinion is pointing down I'm betting you have at least 5 or more degrees difference which may or may not cause driveline vibration.... but it will help wear out your "U" joints with no problem. Axle shims will solve your problem but you'll need to measure the angles first and order the correct ones.

Centerline
HotRodsAndHemis.com

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[Impala383]

My car has coil springs. I tried to adjust upper arms but could get it to move up. I gonna try again. It seems that adjusting rearend at arms would allow it to move up to correct angle. I think something is to tight somewhere not allowing it to move. Yes it is every bit of 5 degrees angled downward. Thanks for reply.

[matts37chev]

didnt know it was coil
(if you didnt do this when you installed them)
I would loosen all bolts, set car back on ground (or some big blocks)
you need the weight of the car on the springs, at ride height, then tighten all the bolts back up
(you may have done this when installed them)

[speedbump]

You need adjustable upper control arms for the rear. Hotchkis doesn't show them for a 71 B body, but they do for a 70. You should call them. Thier stuff is a little pricey but make a huge difference if you are going to make any horsepower. Because your lower arms are longer than the uppers, any time the ride ht. is lowered, the pinion will drop. Aftermarket is the real way to correct your problem, but if it's a driver only, you might be able to "mickey" it to get about 3* down which should live for you.

[Impala383]

I did set car down and tightend them thanks though. Speedbump that makes alot of sense now i looked at it last night and there is no way to adjust it because of the bottom control arms. I will look in to it the adjustable arms. Its just a street car 375 hp 400tq at the most but i am still going to correct angle that kind of stuff will drive me crazy knowing it like that. Thanks once again everyone for your help on here. Best forum ever.

[matts37chev]

making some new adj arms is pretty easy

[Impala383]

How would you do it? I going to google images online to try and get an idea that would be the best way to correct problem.