Front Suspension explained

1Michel

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I check once in a while V8TV and the guy 's (Kevin) explainations are pretty good.

heres a link about the front suspension of a Cutlass hes rebuilding.

http://v8tvshow.com/content/view/561/1/

Theres pretty interesting stuff there.

TT when the guy gets to the steering tie rod part I think it's from Baer brakes. check the system to eliminate the bump steer.

Ok I found it , heres another link for the bump steer thing

http://www.baer.com/products/tie-rods/index.php
What do you think of that?
 
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Read the tech articles up top, most of it's in there. What those things do is allow you to change the outer tie rod position (height) but it does not address a fundamentally incorrectly designed system.
 
Front steer is simply the best for double a arm suspensions but you can do a rear steering rack setup, just make sure the rack is mounted rigidly and not on some flexy brackets with a crappy donut mount. An internal power box is a nice way to do it also, the biggest issue with the stock system, even when tight is that steering valve. It inherently gives you some slop, always!
 
Rear steer is not only bad..... there is even a good thing:

The akerman angle is much more active then with front steer!

The back side, basically, is bump-steer which is in the wrong side!
 
Ackerman angle is the angle of the steering arms. Simply put, it causes the inner wheel (in a corner) to turn sharper than the outboard one.

Pier Paolo, yes but the the ackerman isn't all that important (doesn't have to be very active) unless you do a lot of low speed cornering (london taxi cabs have crazy ackerman :) )

The problem with the rear steer comes with bushing deflection. As you load the outside suspension corner during cornering the bushigns deflect and the lower arm is pushed inwards, however the steering system is not affected and the driver keeps putting input into the steering wheel. What this deflection causes is that the input is increased because the suspension moves in, this gives oversteer under deflefction. A front steering system gives understeer as a result. And understeer is much easier for a driver to control than oversteer (unless you're Schumi :) )
 
TT you measured a front stock suspension correctly before you did the mods. Where was the best position of the steering arms on the stock suspension to avoid bump steer as much as possible ?
 
The bump steer is not only in the steering arms, it's in the centerlink. So you have to adjust both. Adjsuting the steering arms with bumpsteer blocks affects the ackerman geometry. It's best to get the center link straightened out and then fine tune with the steering arm tie rod end height
 
The bump steer is not only in the steering arms, it's in the centerlink. So you have to adjust both. Adjsuting the steering arms with bumpsteer blocks affects the ackerman geometry. It's best to get the center link straightened out and then fine tune with the steering arm tie rod end height

Any ideas on what would be necessary in terms of centerlink ?
 
I know Marc..... I only would like to save some thing of our C3 steering system!:blush:

Of course the most important effect os the steering is the pump (or bump) steer!

In a front steer system is very easy to have some bump-understeer...... and with rubber on the arms.... even load steer in is the right way!
 
I got an adjustable outer tie rod setup like that because I have some bumpsteer, I don't have the money or know how to completely redesign the front suspension, so what is the best I can do with what I got, basically, how much should I drop the outer tie rod to get rid of as much bumpsteer as possible?
I read the bumpsteer sticky, but that is way too involved for what I have time or money for (at least right now)
Thanks
 
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