after installing springs the rear axle becomes out of balance (more than it should from the factory) correct? what makes this shift? right now my rear end does not seem too bad...but im wondering if i put my car back on a lift would there be some movement? just curious...

 

It doesn't "become out of balance", it simply shifts its position under the car slightly (generally moves toward the driver side a little). The math says the amount it moves can't ever be very much, and in any case it will simply stay at the new location just as securely as it stayed in the OE position when the OE springs were still in place.

You'd relocate it if there was a large lateral shift in the axle's position, or possibly to "fix" OE assembly tolerances enough to fit wider tires or maybe even for appearance reasons.


Norm

 

what Norm says is true, it isn't out of balance, the rear end may have shifted over to the drivers side a little. You can do 1 of 2 things, ignore it, or measure and see if it has indeed shifted and more importantly how much if it has. If it has shifted enough to bother you an easy, cheap cure is an adjustable panhard bar. They go for $110-$way more depending on who's you buy. Very easy to install and adjust. Unless you're going to do some hard core track time look for the polyurethane bushings. The rods ends are more secure, but very noisy for a street car. Pull your wheels off and measure from the top of the discs to the frame rail.

 

If you're going to pull your wheels to measure, please make sure to use jack stands under the axle ends to simulate the car being "at rest" so the measurements are true. If you only jack it up and pull the wheels, it will never sit centered.

The rear end can move on its fulcrum enough to cause the vehicle to "dog track" with as little as a 1.5" drop on its center axis. This can create heavy understeer in one direction. Take it from a pro, we set up hundreds of streets cars a month with our alignment system. Please buy a pan hard bar. Even if it has urethane ends... Not only will it correct your vehicles thrust angle, but it will cosmetically make the rear wheels appear even. Simple 30 minutes install and then off to an alignment shop to get your thrust checked (just because the wheels are even does NOT mean the vehicle's rear end is centered to the chassis itself). PM me if you need pricing on the units we recommend to our street customers.

Eric@impulsecars.com