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Pushy-Loose a tale of a poorly setup car (and how to fix it?)

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I am trying to avoid throwing parts at the problem just to throw parts at things.

Given my statement of the push existed both with and without a bumpsteer adjustment I’m not sure what difference further adjustments in that particular category would make.


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I'm just trying to help you Chris - If you have extended ball joints you really need to have the accompanying outer tie rod ends (M-3130-R2 or m-3130-R3) or a bumpsteer kit so that you can keep the toe adjustment within a reasonable range when making adjustments. Your corner entry response may be altered by the toe settings and then again it may be something else in the set up. It doesn't cost any $$$ to make toe adjustments at the track in order to figure out if the alignment is the issue or not. P.S. - bumpsteer issues are when the steering is in the straight ahead position only.
 

Fabman

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I'm just trying to help you Chris - If you have extended ball joints you really need to have the accompanying outer tie rod ends (M-3130-R2 or m-3130-R3) or a bumpsteer kit so that you can keep the toe adjustment within a reasonable range when making adjustments. Your corner entry response may be altered by the toe settings and then again it may be something else in the set up. It doesn't cost any $$$ to make toe adjustments at the track in order to figure out if the alignment is the issue or not. P.S. - bumpsteer issues are when the steering is in the straight ahead position only.
Let me add to that....bump steer is set in the straight ahead position and changes as the wheel is turned because positive caster causes the steering arms to rise and fall as the wheel steers left and right. What having proper bump steer does is add stability/predictability in the straights and in corner entry/exit (super important) but also minimize the bad bump you get while steering particularly as the body is rolling. Especially if its bumping in, which is the kiss of death. I'm not saying this is his problem, I'm just adding some context to your explanation. Sounds to me like he has something else going on, and this isn't helping.
Bad bump-bad bump...whatchya gonna do...headin' for the corner and it pushes right through.
 
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Fabman

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I'm curious though, what kind of bump steer kit failures you are having.
As long as the rods are free and not bound they last forever until either contact is made or a rod end wears out.
 

Fabman

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FWIW I am running OEM-style tie rod ends instead of a BS kit and can't tell a difference compared to when a BS kit was installed. Maybe I can't drive well enough to tell a difference but I can always change back later when I learn :)
Likely because a proper bump steer job wasn't performed.
If it wasn't done with a proper gauge with the springs removed, it wasn't done correctly and almost certainly made the bump worse than it was stock. I've documented this in video's you have probably all seen.
Once you've done it personally and see how much difference a 1/16" shim can make it all becomes very clear. Guessing will not get you where you want to go.
 
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Grant 302

basic and well known psychic
Maybe this pic will help explain the issue with using a tall ball joint without a bumpsteer kit. Using a rough model, I get about 0.14" toe-in on 1/2" compression starting with a level control arm. That's bad.

This should help visualize the variability introduced during suspension travel:

39772119301_2b02b7d8c1.jpg
 

captdistraction

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I'm curious though, what kind of bump steer kit failures you are having.
As long as the rods are free and not bound they last forever until either contact is made or a rod end wears out.

My steeda kit bound the rod-ends on the spacers, causing them to yield. The MM/Ford Racing kits have had stud failures. That said, to please all I bought a FTR kit and will have it here soon. That said I didn't notice a change in the entry/mid push with or without the kit. I had previously set the kit with a homemade bumpsteer gauge and believe the measurement to have been very close to correct.

While it might be a contributor, I don't think that's the only cause of my issues.
 
My steeda kit bound the rod-ends on the spacers, causing them to yield. The MM/Ford Racing kits have had stud failures. That said, to please all I bought a FTR kit and will have it here soon. That said I didn't notice a change in the entry/mid push with or without the kit. I had previously set the kit with a homemade bumpsteer gauge and believe the measurement to have been very close to correct.

While it might be a contributor, I don't think that's the only cause of my issues.

Drill your spindles and install a bolt through kit.

http://www.maximummotorsports.com/Conversion-kit-from-tapered-stud-to-bolt-through-spindle-P569.aspx
 
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Maybe not..uhmm if you ran the grade 8 bolt through, nutted it, or better yet created a nut with a shoulder type of affair that you could also use as the spacer...then the heim, then a lock nut, I don't think that would happen as long as the bolt fit the hole properly...now that you've got me thinking about it.
I think that's sort of what the MM kit does, it's hard to tell from the pic
Where's Fabman?
 

Fabman

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Maybe not..uhmm if you ran the grade 8 bolt through, nutted it, or better yet created a nut with a shoulder type of affair that you could also use as the spacer...then the heim, then a lock nut, I don't think that would happen as long as the bolt fit the hole properly...now that you've got me thinking about it.
I think that's sort of what the MM kit does, it's hard to tell from the pic
Where's Fabman?
Done it that way for decades....this is the first time I've used the little taper attachment.
Maybe there is an issue with the steering arms on the s197 that I am unaware of...but as far as the camaro/chevelle/pinto style spindles there was always plenty of meat.
 
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Rob's got a good add. I always found the problems on front steer set ups vs rear steer linkage plus these are strut cars running 7 to 8 degrees positive caster not SLA running 3 to 5 degrees positive. JS
 

Fabman

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Rob's got a good add. I always found the problems on front steer set ups vs rear steer linkage plus these are strut cars running 7 to 8 degrees positive caster not SLA running 3 to 5 degrees positive. JS
Did plenty of strut cars too. Front steer, rear steer and my personal favorite, rear steer with front steer added. When setting bump, I would use shims to correct the bump, then measure the final stack and machine a single spacer with a tapered bottom to clears the rod end body (one sized correctly for each side) and use that solid spacer. That way in the heat of the moment during a repair or whatever you don't have to worry about dropping the shims and losing your settings. Comes in super handy for when you are building cars for other people you don't have to worry about them mixing up the shims and effing up your work.

Yes, you are correct to point out that the more caster, the more the steering arms rise and fall which alters the bump and also increases the likely hood of encountering a bind.

HOWEVER...if you are doing this correctly and are setting the bump with the springs removed you can easily jack the suspension through full bump and jounce and grab the tie rod at both extremes and steer full left and right and check that the rod ends still rotate freely. If you do this, and there is 100% no bind, you will have no failures.
 
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Biggest thing that I noticed when doing a bumpsteer correction is that when the suspension is in droop that some cars limit out on droop at the heim on the outer tie rod ends instead of the shock/strut or other suspension stop.
 

Fabman

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Here is one of my front steer-rear steer cars.
Strut rods going towards the front and a front mounted steering rack. You don't see much of this, but it's the BEST way to do it in my opinion. The reason most manufacturers/car builders don't do this is for packaging. There is a lot going on up front and stuff tends to be in the way of each other. Why is it better to have the strut rods in front? Ever try shooting pool with a rope? It works best when it's pulled tight rather than pushed. It takes a lot more rigid parts to make the rearward struts strong enough plus when loaded they want to be anything but straight. When you pull on them they always want to be straight.
Can you do it either way successfully? Of course you can. My way is just better. :)

540796_10150994698763535_2053165924_n.jpg
 

Fabman

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Biggest thing that I noticed when doing a bumpsteer correction is that when the suspension is in droop that some cars limit out on droop at the heim on the outer tie rod ends instead of the shock/strut or other suspension stop.
In my experience I never had one I couldn't free up with a little planning.
 

Fabman

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Here we go...this is the rear view of a front steer/rear steer setup.
Notice that the sway bar is mounted to the bottom of the control arm for better packaging. Also notice the lack of a rod end or spacer in the link. That's because on oval track cars the sway bar is only designed to work in one direction.
This is the right front, so being mounted on the bottom of the control arm, it is the pulling side, so, no spacer.

165845_10150994698893535_2056183076_n.jpg
 
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