bumper steer question

What modifications have you done to the stock suspension? People usually install BSK's after they have lowered it because it changes the geometry of the tie-rods. Another option is extended ball joints.

Describe some of the steering problems you are having? It could be bad inner/outer tie-rods that is making your car steer so bad. A bad alignment and bad ties can make it do the same.

Tim

Just get some el-cheapo polyurethane offset rack bushings first. It was enough for my combo. See if it cures your problem.

Setting up BSK's can be a bear so I hear.

Ttt

I would check your Balljoints and tie rod ends first. If they are worn or have a lot of play in them, you car will exhibit the symptoms you are describing. The play in the ball joints basically allows the car to steer itself. Very wide, low profile tires will also exacerbate the problem. I have always found that ANY car, with very wide tires will jog lanes if the ruts are deep enough.

Hope this helps

wazazzle said:

when i drive on the highway, some lanes have those deep grooves from semitrucks. when ever i'm in those lanes it like the steering yanks out of my hand and weaves into other lanes-n-$hit. even if i fight it. i can literally feel when i'm riding up or down a grooves. all stock susp so far.

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Bump steer kits would not help that condition much if any, more than likely it is related to tie rod ends, worn bushings or ball joints.

The bump steer kits will bring the steering rod ends back to normal levels when a car is lowered. What this does is when the suspension is moving up and down the angle of the steering rod either moves up or down and in a sense shortens it length. This will pull the wheels in (cause toe in) as this happens. By having the steering rods level or at the medium of travel of the suspension the amount of change is less. When a car has been lowered the steering rods are not sitting level and they are higher from level on the outside extremes. Therefore as your suspension is compressed on a given side it will pull that wheel in at a faster rate because of the angle that is already there from the lowering of the car. On the extension side of the suspension it will actually push the wheel out (toe out) as the effected wheel is in suspension travel. A bump steer kit will bring the steering rod level and the toe in condition will improve and the toe out condition will be eliminated.

As a simple example of what is happening, take a pencil and lay it flat on a table. This represents your steering rod at an ideal position on your car. Now hold another pencil perpendicular to one end of the pencil laying flat on the table. The perpendicular pencil will represent the position of the steering rod end. Raise the end of the pencil laying flat next to the perpendicular pencil up to about 15 degrees and notice how much distance the pencil tip moved in length from its flat position on the table (this will be the distance from the tip of the angled pencil to the perpendicular pencil). Lets just estimate that at about 1/4 of an inch. Now, raise it another 15 degrees and notice the distance the tip moved in length away from the perpendicular pencil. That distance is now close to 1 inch, so the second 15 degrees moved the end of the pencil in a lateral direction of a distance 3 to 4 times more than the first 15 degrees of movement.

Although your steering rods are not changing angles as much as this example the same effects are happening. So when you lower your car the steering rod is put at an angle and when your suspension is compressed it's bump steer angle has increased at a larger rate than if the steering rod had been set correctly with a bump steer kit.

Get down under the car with a 7/8 boxwrench and undo the jam nuts on the inner tie rods on the steering rack. Grab the inner tie rod with locking pliers and turn them inward (follow the threads, you're trying to make them "shorter"). This adds toe-in. Got the same exact number of turns on both sides (index them)...like 1-2 turns. Now your car will be much more stable but will eat some tire in the long run if you went too far. The toe in makes it very stable.

My car exibits all the same symptoms and I'm running out of options. I have stock springs. I have done the sn95 5 lug conversion spindles. '03 cobra wheels (17x9) with 245/45/17 wheels. Brand new sn95 ball joints. Poly rack bushings (didn't help), Steeda bump steer kit (didn't help), Steeda C/C plates (didn't help). I have replaced my steering rack with a replacement rack from Advance auto which may be the source of all my problems, I don't know. Could it be control arm bushings? I have not replaced those. I'm running out of crap to replace and I'm at my wits end. Somebody help!!!!

wazazzle said:

thanks guys for the help seeing how its all stock. it's probably best if install new steering rack, should correct probl. will install c/c kit when springs installed too.

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I hate to say it...but I think the only way your going to correct the problem is to run more narrow tires. The issue you are having is called trammeling. As stated before, it is a result of having wide front tires. The tires are to wide for the grooves in the road, so they constantly wonder up and down the groove. Being to wide, they wont stabilize until that narrow road groove is gone…or widens to the point in which it becomes wider that your tires.

I have all new front suspension components (less than 2 yrs), and it did nothing to alleviate the problem. You may have a bit of luck by replacing your rag joint in your steering linkage. It wouldn’t cure the problem, but it would help take some slack out of the steering system if you have any.

Increase toe in dude!

Reduces the effect of the tramlining as well. Trust me on this one. Before I did this, my 225/60/r15 factory tires would tramline on rte 2 out near lexington where they have some wicked grooves in the highway. 1 1/2 turns in on each tie rod and it's gone.

crazypete said:

Increase toe in dude!

Reduces the effect of the tramlining as well. Trust me on this one. Before I did this, my 225/60/r15 factory tires would tramline on rte 2 out near lexington where they have some wicked grooves in the highway. 1 1/2 turns in on each tie rod and it's gone.

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And you will also increase understeer…as well as drag and excess tire wear. I've been in stock ls1's which had bad trammeling problems (stock). Some roads just suck worse than others.

Slop in the steering system will make it difficult to control trammeling. That is the first area I would look into.

Something for something. The factory setup is that way for a reason and deviation from it will incur some sort of compromise. I say if you can afford to fill your car with racing parts then you can afford to switch tires a bit more often than usual.

crazypete said:

Something for something. The factory setup is that way for a reason and deviation from it will incur some sort of compromise. I say if you can afford to fill your car with racing parts then you can afford to switch tires a bit more often than usual.

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Or just leave it and live with the problem. My suspension went on to reduce weight and increase cornering capabilities. I would be negating the effects of the improved suspension and geometry by increasing toe in to combat a problem that exists on all vehicles which have wide front tires.