|
Re: 71 Charger Bump Steer?!?!?!
[Re: moparx]
#3195547
12/05/23 08:15 PM
12/05/23 08:15 PM
|
Joined: Dec 2014
Posts: 5,812
ohio
ruderunner
master
|
master
Joined: Dec 2014
Posts: 5,812
ohio
|
Nascar guys figured this out a long time ago. Go find a straight axle housing from them.
Angry white pureblood male
|
|
|
Re: 71 Charger Bump Steer?!?!?!
[Re: Kelob_pie]
#3196010
12/08/23 02:14 AM
12/08/23 02:14 AM
|
Joined: Jan 2003
Posts: 27,467
So Cal
autoxcuda
Too Many Posts
|
Too Many Posts
Joined: Jan 2003
Posts: 27,467
So Cal
|
Hi Guys-
Been a long time since I've been on here. Finally getting back to my projects.
Anyways, I have a beater 71 Charger 383 that I bought maybe 10 years ago. So I finally got it road worthy, installed new front end pieces.
New QA1 upper and lower control arms, QA1 tie rod ends, QA1 strut rods, new shocks, ball joints, etc. New Borgeson steering box and pitman arm/tie rod as well.... new tires wheels as well......
So I took it to the alignment shop and we gave it -.5 degrees per side of negative camber, and plus 3.5 of caster. 1/16th of toe in...
Drove nicely on a flat road near the alignment shop. Big thumbs up.
Trailered it home and wanted to show off to my daughter what a nice driving machine this was, and I hit some minor bumps and grooves on the road and this thing is all over!!!!!!!
MAJOR bump steer! The only thing that I question is when I installed everything, my center link was not parallel to the street anymore due to the pitman arm being lower than my idler arm. I didn't think anything at the time because I thought "no big deal, everything is on ball joints"
So, could this be causing bump steer???????
Thanks for any info!
Your idler arm is not a ball joint. It's a plain bearing that only rotates around one axis. If your centerlink is angled, the idler has some binding. May not be that apparent in resistance, but will wear things wrong and change the bumpsteer because the inner tie rod is moved up or down from stock. You have the wrong pitman or idler in your car. I did that once putting an E-body pitman I had laying around in an A-body. The centerlink was angled. OR your Borgeson steering box is tilting your pitman the wrong way OR the splines on the output shaft are moving you pitman into the wrong place (was a common issue with the 1st units)
Last edited by autoxcuda; 03/20/24 11:27 AM.
|
|
|
Re: 71 Charger Bump Steer?!?!?!
[Re: autoxcuda]
#3196013
12/08/23 06:41 AM
12/08/23 06:41 AM
|
Joined: Dec 2003
Posts: 22,696
Bitopia
jcc
If you can't dazzle em with diamonds..
|
If you can't dazzle em with diamonds..
Joined: Dec 2003
Posts: 22,696
Bitopia
|
Well yes and no IMO. Most bump steer measurements are taken I believe with wheels pointed straight, and if both links are not parallel with the LCA and located inline with ball joints and pivot points, bump steer is present. I suspect its possible one side could be relatively bump steer free and the other side not to be, if any of the three conditions you note are present. I believe once straight-ahead bump steer on both sides is corrected/improved, any steering issues regarding binding, accelerated wear, etc will have already been resolved. What I can't wrap my head around yet is if both sides could have exactly opposite bump steer problems, effectively canceling out normal observed bump steer issues while driving. 
Reality check, that half the population is smarter then 50% of the people and it's a constantly contested fact.
|
|
|
Re: 71 Charger Bump Steer?!?!?!
[Re: jcc]
#3196207
12/09/23 08:03 AM
12/09/23 08:03 AM
|
Joined: Dec 2014
Posts: 5,812
ohio
ruderunner
master
|
master
Joined: Dec 2014
Posts: 5,812
ohio
|
If I follow what you're saying, then yes it's possible that total toe wouldn't change (one side toes out, the other toes in) but there would be some side effect. For example, if the vehicle goes straight, the steering wheel would rotate one way or the other, conversely, if the steering wheel doesn't rotate, the car will change direction.
This is often seen on lifted straight axle trucks. More often on one's with push pull drag links that don't follow the spring arc.
Toe changes that would be less noticeable would be if both wheels toe in or out equal amounts. The car would still go straight and the steering wheel wouldn't rotate. This would be noticeable however on roads with uneven traction. Say a patch of ice on an otherwise dry road. The tire with better grip will steer the car as the other slips.
Angry white pureblood male
|
|
|
Re: 71 Charger Bump Steer?!?!?!
[Re: ruderunner]
#3196332
12/09/23 07:36 PM
12/09/23 07:36 PM
|
Joined: Dec 2003
Posts: 22,696
Bitopia
jcc
If you can't dazzle em with diamonds..
|
If you can't dazzle em with diamonds..
Joined: Dec 2003
Posts: 22,696
Bitopia
|
Yes we agree. that likely would circle back to a thrust angle issue?, but still not a bump steer issue.
Reality check, that half the population is smarter then 50% of the people and it's a constantly contested fact.
|
|
|
Re: 71 Charger Bump Steer?!?!?!
[Re: jcc]
#3221480
03/19/24 04:45 PM
03/19/24 04:45 PM
|
Joined: Mar 2005
Posts: 1,545
Seattle, WA
375inStroke
Special needs person
|
Special needs person
Joined: Mar 2005
Posts: 1,545
Seattle, WA
|
Is it possible you have a '70 K-frame? Hard to tell with the Schumacher steering box. The stock box should be in a straight line with the steering column. The box is mounted at a different angle for '70 B-body compared to E-body and your car. Jumping around hitting bumps isn't the definition of bump steer. Either move the wheel up and down, and measure the toe change, or try to drive the car in an open area turning, and hit the brakes. The wheel jounce will turn the car in or out of the turn if there's bump steer. If parts are all correct, you can correct bump steer by shimming the steering box to move the pitman arm up or down, or slot the idler arm mount, and weld washers to locate it once you adjust all the bump steer out. Yes, it'll take time, but looking into the K-frame would be my first step. When I get home, I'll look at my stuff and tell you which is which. There's an indentention on the steering box mount for one body that's not on the other, but can't remember which.
Last edited by 375inStroke; 03/20/24 09:00 AM.
|
|
|
Re: 71 Charger Bump Steer?!?!?!
[Re: 375inStroke]
#3221637
03/20/24 11:39 AM
03/20/24 11:39 AM
|
Joined: Jan 2003
Posts: 27,467
So Cal
autoxcuda
Too Many Posts
|
Too Many Posts
Joined: Jan 2003
Posts: 27,467
So Cal
|
Is it possible you have a '70 K-frame? Hard to tell with the Schumacher steering box. The stock box should be in a straight line with the steering column. The box is mounted at a different angle for '70 B-body compared to E-body and your car. Jumping around hitting bumps isn't the definition of bump steer. Either move the wheel up and down, and measure the toe change, or try to drive the car in an open area turning, and hit the brakes. The wheel jounce will turn the car in or out of the turn if there's bump steer. If parts are all correct, you can correct bump steer by shimming the steering box to move the pitman arm up or down, or slot the idler arm mount, and weld washers to locate it once you adjust all the bump steer out. Yes, it'll take time, but looking into the K-frame would be my first step. When I get home, I'll look at my stuff and tell you which is which. There's an indentention on the steering box mount for one body that's not on the other, but can't remember which. Since the '70 K-frame also contains the idler mount and LCA pick up points, swapping K-members will not change bump steer. Most of the critical things that effect bump steer are being changed as a whole. It will change the box to steering column angle. But that doesn't effect bump steer.
Last edited by autoxcuda; 03/20/24 11:50 AM.
|
|
|
|
|
