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///Mcompact · 11-29-2008, 06:48 PM

It looks like you've lowered it quite a bit. You'll need to adjust the roll center of the front end. When your suspension is compressed, one of the three links (most likely tie-rod) to keep your wheels on the axis is unequal in length (or not centered anymore) and is causing toe out/in, making your tires turn without any input from your steering wheel.

With Evos, we use taller Tie-rod ends to lower the rod back to zero roll center to offset the angles from lowering the front-end (in our case..the tie-rod is back to parallel to the ground instead of angled up). I have coilovers, but didn't lower my car much at all because I didn't want to mess with the geometry. Automakers (as of late) design the suspension to have very little bump steer, but once you lower it, you run into it.

You can even have bumpsteer issues in the rear. I do have the rear of my car lowered a bit and there is bumpsteergoing on back there when I'm close to lifting a tire at an AX event (decompressed), but it's not something I run into on the streets. It is fixed by using a corrected control arm bushing.

So you can either raise it back to stock height and realign the wheels or correct the roll center by figuring out which suspension link is pulling/pushing your wheels during compression and install the correcting part. There are a lot of lowered mustangs, so there has to be a aftermarket solution to fixing the bumpsteer...and getting a final alignment accomplished.

**Edit** Here you go:
http://www.steeda.com/products/bumpsteer_kit.php

11-29-2008, 06:48 PM	#3
///Mcompact SQUIRREL OVERLORD Join Date: Feb 2007 Location: Nunya bidness Posts: 1,382	It looks like you've lowered it quite a bit. You'll need to adjust the roll center of the front end. When your suspension is compressed, one of the three links (most likely tie-rod) to keep your wheels on the axis is unequal in length (or not centered anymore) and is causing toe out/in, making your tires turn without any input from your steering wheel. With Evos, we use taller Tie-rod ends to lower the rod back to zero roll center to offset the angles from lowering the front-end (in our case..the tie-rod is back to parallel to the ground instead of angled up). I have coilovers, but didn't lower my car much at all because I didn't want to mess with the geometry. Automakers (as of late) design the suspension to have very little bump steer, but once you lower it, you run into it. You can even have bumpsteer issues in the rear. I do have the rear of my car lowered a bit and there is bumpsteergoing on back there when I'm close to lifting a tire at an AX event (decompressed), but it's not something I run into on the streets. It is fixed by using a corrected control arm bushing. So you can either raise it back to stock height and realign the wheels or correct the roll center by figuring out which suspension link is pulling/pushing your wheels during compression and install the correcting part. There are a lot of lowered mustangs, so there has to be a aftermarket solution to fixing the bumpsteer...and getting a final alignment accomplished. Edit Here you go: http://www.steeda.com/products/bumpsteer_kit.php Last edited by ///Mcompact; 11-29-2008 at 07:02 PM.