Have a novice susp question .........Bump Steer with 66 Chevelle stock spindles ..... I see some kits on market that replace your outer tie rods with rod ends and spacers etc allowing some adjustment to improve potential bump steer ............what geometry are you shooting for ??...assume you set up with susp fully loaded ??

Bill

They don't really work on a Chevelle chassis... they only allow adjustment downward when you really need to go upward with the outer pivot point.

They don't really work on a Chevelle chassis... they only allow adjustment downward when you really need to go upward with the outer pivot point.

Thanks

Should I assume this still the case with aftermarket control arms / steering arms but stock spindle


...... so if they could go up what are you trying to get a level outer tie rod to inner pivot ??

You have aftermarket steering arms? What brand (I'm not aware of any, other than ATS for their AFX spindle)

You want the tie rod ends parallel in front view to an imaginary line that would connect the pivot of the lower balljoint to the center of the lower A-arm bushings.

"the tie rod ends parallel in front view to an imaginary line that would connect the pivot of the lower balljoint to the center of the lower A-arm bushings."

OK thanks alot,thats the info I was looking for and assume when chassis loaded at ride height

My car more drag race than pro touring I use TRZ lightweigt tubular control arms ....they also make alum steering arms to help to improve geometry / steer straight after front changes quickly with weight transfer / bump steer ..... I just trying to better understand what the correct geomerty should be and not make it worse

Thanks again I think I got it

I was just browsing TRZ's website, and looking at their steer arms. They appear to lower the tie rod pivot, which would make bumpsteer worse with stock type steering unless they flipped the taper to run the tie-rod on the top side. :confused:

Sure looks that way now that you have explained it to me .......I do know the pics of the bump steer kit shown for the stock chevlle spindle is incorrect ........it's the pinto rack kit ..........Now that I understand the concept better I will can ask better questions I have some stuff coming from them will give Mike a call to better understand what they selling

Thanks for your help , appreciate it

"the tie rod ends parallel in front view to an imaginary line that would connect the pivot of the lower balljoint to the center of the lower A-arm bushings."

OK thanks alot,thats the info I was looking for and assume when chassis loaded at ride height
As I understand it:

If you disallow bushing deflection and control arm flex under load--ride height won't make any difference IF (big IF) the pivot points for the tie rods are where they need to be.

IF the pivot points for the inner tie rod ends are positioned properly, the tie rod will be parallel to the ball joint/bushing line no matter where the suspension is in the jounce/rebound curve.

I'm thinking you need to imagine the lower control arm pivot line (bushing centerlines) as seen from the top or the bottom (one-dimensionally); and mentally extend the pivot line to where it intersects with the tie rod (wheels straight ahead)--that's where the inner tie rod pivot should be. Of course the actual position will be above that imaginary line by the amount that the outer tie rod end is above the ball joint.

Disagreement???

Here`s a very simplified bumpsteer diagram that should help iron things out a bit. Note that ANY median tie rod height will work provided that it`s angle will make a line drawn through it`s pickup points (pivots of the inner and outter toe rod ends) intersect with the instant center and the length puts the inner and outter tie rod end pivots in the proper horizontal position. On stock A bodys the outter pickup point (in the tie rod end) is too low and the line drawn throught it shoots over top of the instant center. Raising it changes the angle and can bring it back on target, lowering it with a bumpsteer kit would make it shoot even higher over the instant center (IC) making bumpsteer worse. We use a taller lower ball joints to raise the spindle,steering arm and outter tie rod end into the proper location. It`s a happy accident that it also improves the camber curves,RC location and lateral RC migration as well. :) Mark SC&C

http://www.longacreracing.com/articles/text/bsdrawing.jpg

This great stuff guys ......... appreciate it .... I was lying under car last nite visualizing the correct line and what would need to be modified and looked to me should not matter chassis loaded or not .......currently engine out and car up on a stand susp hanging free ........ so the steering arm tie rod end attatch point needs to be higher with no change in outer attatch height point correct ??

Here`s a very simplified bumpsteer diagram that should help iron things out a bit... Mark SC&C

Holy Crap! That's WAY different than what I was thinking.

Is the tie rod end aimed at the Instant Center even when the Instant Center is moving around due to jounce/rebound?

FYI on steering arms, here's another set-up by AUTOFAB but probably track only: http://autofabcart.net/afrc-steeringarms.aspx Click on the image 2.

Any such thing as a Gulstrand-type of Mod for A-Bodys? This mod is (was?) for early Camaro's and it was an inexpensive 80's 'kinda-fix' based on relocating the factory's upper a-arm attachment points. Kept the OEM suspension pieces.

The TRZ arms use tubular outer tie rod with rod end that allows you to install on top or under the steering arm to get the correct geometry, not a tapered hole ......I have the parts and doing install right now .the autofab looks similar in concept

FYI on steering arms, here's another set-up by AUTOFAB but probably track only: http://autofabcart.net/afrc-steeringarms.aspx Click on the image 2.

Any such thing as a Gulstrand-type of Mod for A-Bodys? This mod is (was?) for early Camaro's and it was an inexpensive 80's 'kinda-fix' based on relocating the factory's upper a-arm attachment points. Kept the OEM suspension pieces.

No, no "G" mod or "Shelby" mod for "A" bodies.