Anyone ever install a bumpsteer kit?

[ScoJack]

Ive got my GN half torn apart in my boss's garage. Got the whole passenger's side suspension rebuilt. Purchased a bumpsteer kit from Speedway Motors and got the adapters from Spohn. Any of you guys ever done this? Im looking for how exactly to set it up. Got all new stuff, everything. I seem to remember being told to have the tie rod end as parallel to the control arm as possible?

Going to be finishing up this job tomorrow.

Thanks!

Scott

[2gofaster]

Honestly, bumpsteer is one of those things you're peeing in the wind trying to set up without measuring. It's at best a shot in the dark otherwise. You have to take your springs out, too. Without the correct tools, this is what I'd do:

1. Put floor jack under kmember and Take the springs out.
2. take 4 12x12 floor tiles. Smear grease on 2 of them. Place one of the other tiles on top of each greased tile and put the pair under each front tire.
3. drop car back to ride height
4. With helper set toe across front and back of tires to desired amount
5. raise car 1", 2", 3" and measure toe at each
6. drop car back to ride height, then lower car 1", 2" 3" and measure toe at each
7. Add spacers to bump steer tie rod end and repeat steps 5 and 6 all over again for each spacer set
8. Pick spacer set that gives you least overall change in toe

Doing this correctly could take all day.

[ScoJack]

I dont think I want to take the springs out after I just rebuilt everything.



Thanks for the tips. I'll see what I can do.

[2gofaster]

Unless you're willing to do that, unless someone has the exact same setup as you down to ride height and suspension componentry then you are at best guessing. Just leveling the arms with the control arm doesn't guarantee the smallest amount of bumpsteer.

[keithq69]

2gofaster is right.
If you don't want to actually measure the toe change then you're best to just run the stock tie rod end. There is no way to know the effects without measuring.
I know it's a pain in the butt, if you want it set up right it's a days work and then you're done. Worth it I think.

[Bryce]

The other option would be to lay out the suspension pickup points in a suspension program and dial it in then install it at teh calculated dimensions.

[gsxrken]

Measure your suspension at ride height in such a way that you can recreate ride height with the car on jack stands and your coil spring removed. You then throw a jack under the control arm and raise it up to "ride height" and afix a dial indicator to read your brake disc face, and then measure how much it moves as you raise and then lower the control arm about 3" in each direction. Bump steer is simply the tie rod tugging or pushing on the steering spindle as it goes up or down. By juggling spacers in the bump steer kit, you should be able to just about eliminate or at least center the changes so that they are the same in jounce and droop.
In reality, with a stiff setup that a Lowered car probably has, you won't have too much travel. In that limited travel, you should be able to get it to where its barely noticeable.

[David Pozzi]

An alignment shop can pull down on the chassis and take measurements.
At home you would need to have the car aligned, have an accurate way to measure toe, and the tires must be on a very slippery surface like stacked sheets of waxed paper with soap or grease between them. Ideally it should be on alignment turntables.

You need to raise the car and measure toe at least every inch. to go lower at home, you can open the hood, place cardboard or padding on the radiator support 7 fenders, then stack heavy stuff like cyl heads, flywheels, tool boxes, fat friends, - whatever. stack it on evenly and measure toe every inch.

If the car is front steer and toes in with the suspension in bump, the outer tie rod needs to be lower, If it toes out, the outer tie rod needs to be higher.

For rear steer cars, it's the reverse, lower for excessive toe out, higher for toe in. If plotted out on a graph, it can also indicate if the tie rod length is correct, - it will change the shape of the curve.
David

[Rod]

I dont think I want to take the springs out after I just rebuilt everything.

Thanks for the tips. I'll see what I can do.

to get your suspension right rebuilt or not you will take it apart many-many times I had my front suspension apart during my build maybe 4 times or so and since it has been on the road (2 years) maybe 2 or 3 times more reducing striction, adding bearings, changing 3 different height upper ball joints, Guldstrand, half Guldstrand, my own strand!, and so on....you have had some good advice handed to you and that david pozzi guys a pretty good suspension guy also, a little work now is a lot of race/driving fun later