Re: Excessive toe-in???
[Re: superwrench]
#2753142
03/18/20 01:48 PM
03/18/20 01:48 PM
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Joined: Aug 2003
Posts: 43,123 Bend,OR USA
Cab_Burge
I Win
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I Win
Joined: Aug 2003
Posts: 43,123
Bend,OR USA
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That can be fixed by reshaping the tie rods, one of the Mopar drag race chassis manuals covered that I remember hearing one of the more serious NHRA Mopar stock racers saying he had got his car set up so it had a max of 1/8 inch toe change from max front end low to wheels off the ground I've never tried doing that though.
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
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Re: Excessive toe-in???
[Re: topside]
#2753171
03/18/20 03:17 PM
03/18/20 03:17 PM
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Joined: Jun 2005
Posts: 5,102 Western Md.
skicker
"The Champ"
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"The Champ"
Joined: Jun 2005
Posts: 5,102
Western Md.
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The terminology for what your experiencing is bump steer...
Its basically the movement of a spindle (tow-in to tow-out) from full jounce to full extension...
The individual ride height of any given car will affect this.
One part of this is the tie rod attachment at the spindle is often in too low or too high of a relation to the idler and pittman arms.
I have lowered the idler and pittman arms in the past to lessen the bump steer...
FWIW this was on a dirt car which may have had a higher than normal ride height...
You can purchase a bump steer gauge at Speedway but all adjustments pretty much require all aftermarket steering components...
We used 5/8" diameter spacers of different thicknesses under a hiem joint that replaced a factory tie rod end...
Typically you need to have the spindles drilled out to 5/8" to utilize this design...
The 2nd aspect is the attachment point of the inner tie rod...not only vertical but also left to right...
I know with a GM they also weld new "lugs" onto an existing drag link to relocate the inner tie rod ends...
Using the gauge and modify-relocating the steering pivot points will allow for near zero bump steer but it will take a lot of work to get it that precise...
Then you get to do it to the other side as well...
...FAFO...
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Re: Excessive toe-in???
[Re: skicker]
#2753177
03/18/20 03:43 PM
03/18/20 03:43 PM
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Joined: Jan 2003
Posts: 20,167 Park Forest, IL
slantzilla
Too Many Posts
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Too Many Posts
Joined: Jan 2003
Posts: 20,167
Park Forest, IL
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Watch video of a stock suspension Mopar come down from a wheelstand. It's a trainwreck. Older Ford is worse.
"Everybody funny, now you funny too."
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Re: Excessive toe-in???
[Re: slantzilla]
#2753237
03/18/20 07:06 PM
03/18/20 07:06 PM
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Joined: Aug 2011
Posts: 2,853 Pattison Texas
CSK
master
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master
Joined: Aug 2011
Posts: 2,853
Pattison Texas
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The old DC race manual, shows what to do, you bend the arm on the lower Ball joint up or down to get the bumpsteer better, I bent mine down 1 inch & it is MUCH better now.
1968 Charger COLD A/C Hilborn EFI 512ci 9.7 compression, Stealth heads, 4.10 gear A518 ODtrans 4100lb,10.93 full street car trim 2020 T/A 392 Stock 11.79 @ 114.5
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Re: Excessive toe-in???
[Re: topside]
#2753245
03/18/20 07:21 PM
03/18/20 07:21 PM
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Joined: Oct 2003
Posts: 2,537 PORT ALBERNI , BC., CANADA
superwrench
OP
master
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OP
master
Joined: Oct 2003
Posts: 2,537
PORT ALBERNI , BC., CANADA
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Actually 1 9/32" to be precise. I have always had E and B Bodies and have noticed a slight deflection but never anything like these A Bodies. Just wondering where a good point on the travel would be to set the toe when racing...2" rise maybe and set it to 0 ???
Last edited by superwrench; 03/18/20 07:25 PM.
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Re: Excessive toe-in???
[Re: A727Tflite]
#2753379
03/19/20 08:26 AM
03/19/20 08:26 AM
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Joined: Jun 2005
Posts: 5,102 Western Md.
skicker
"The Champ"
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"The Champ"
Joined: Jun 2005
Posts: 5,102
Western Md.
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The static ride height will also play a part...the lower the car is the worse the problem gets when the front end is extended... The higher the ride height the less noticeable it is...
...FAFO...
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Re: Excessive toe-in???
[Re: A727Tflite]
#2753381
03/19/20 08:46 AM
03/19/20 08:46 AM
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Joined: Mar 2011
Posts: 3,069 Michigan
A727Tflite
master
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master
Joined: Mar 2011
Posts: 3,069
Michigan
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The shop behind the old “Woodward Garage” run by two suspension guys from Chrysler Engineering used to set the toe with the driver’s weight in the front seat and with the car 1” up from normal ride height. And heating and bending cams from his shop as well. First time I ever saw it done was in early 1967 on our SS car.
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Re: Excessive toe-in???
[Re: eds dart]
#2753618
03/19/20 08:02 PM
03/19/20 08:02 PM
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Joined: Apr 2006
Posts: 4,220 West Plains, MO
DrCharles
master
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master
Joined: Apr 2006
Posts: 4,220
West Plains, MO
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now 4 degrees of caster is probably too much for a street car, especially with man steering. on a race car works great. My '72 Dart big-block has tubular UCAs, 3.5 caster and a 16:1 manual box. Handles as well on the street as a B engine A body can Steering is somewhat heavy but only really noticeable if the car is not moving
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Re: Excessive toe-in???
[Re: DrCharles]
#2753797
03/20/20 12:14 PM
03/20/20 12:14 PM
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Joined: Oct 2003
Posts: 2,537 PORT ALBERNI , BC., CANADA
superwrench
OP
master
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OP
master
Joined: Oct 2003
Posts: 2,537
PORT ALBERNI , BC., CANADA
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now 4 degrees of caster is probably too much for a street car, especially with man steering. on a race car works great. My '72 Dart big-block has tubular UCAs, 3.5 caster and a 16:1 manual box. Handles as well on the street as a B engine A body can Steering is somewhat heavy but only really noticeable if the car is not moving What brand??/ I see Hotchkiss has some...pricey though...
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Re: Excessive toe-in???
[Re: DrCharles]
#2754104
03/21/20 10:23 AM
03/21/20 10:23 AM
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Joined: Mar 2006
Posts: 9,824 MI, usa
dvw
master
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master
Joined: Mar 2006
Posts: 9,824
MI, usa
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Read here; http://www.longacreracing.com/technical-articles.aspx?item=8162Moving the tie rods down is easy. You can add caster. Or the outer tie rods can be replaced with heim joints and use a spacer. If the outer tie rod is to low reducing Caster will bring them up. Anything else is more than likely going to require bending the outer tie rod attachment point. So with our type of suspension that means bending the steering arm section of the lower ball joint. The other item I see on A bodys is that many times the front suspension is raised quite a bit. The arc of the upper control arms now pulls the upper ball joint in during rebound (extension) causing extreme negative camber. Camber affects toe. A taller spindle would help in this situation (FMJ body). Also mentioned earlier was the in/out oscillation of the wheels coming down from a wheel stand. This is NOT a Mopar only issue. Many have theories as to the cause. Here's mine: As the suspension rises the track narrows. The natural arc of the control arms makes this inevitable. The track width is now narrower. When the tires come back into contact with the ground they push and scrub outward to return to the natural track width. During this process the bushings are compressed, steering linkage flexed ( especially the idler arm pivot up/down), frame rail and control arm flex also. This causes the toe to oscillate positive/negative. The best cure I've used is to add compression to the front shocks. This allows the front suspension to settle slowly. This in itself is a benefit of not unloading the rear tires. You can get them right with some work. Mine stays straight as an arrow Doug
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Re: Excessive toe-in???
[Re: A727Tflite]
#2754133
03/21/20 11:46 AM
03/21/20 11:46 AM
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Joined: Jan 2003
Posts: 5,387 Pikes Peak Country
TC@HP2
master
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master
Joined: Jan 2003
Posts: 5,387
Pikes Peak Country
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Toe changes are primarily caused by four conditions; outer tie rod too low or too high and tie rod length too long or too short. Items like this, and others attached to the link, allow the tie rod ends to be relocated up or down, provided you get the correct style of spacer to mate with the steering arm and tie rod taper. If you have rod end tie rods, this adjustment is even easier with a thru-bolt arrangement. This relocation accomplishes the same thing as heating and bending the steering arm to relocate the outer tie rod pivot point. Of course for some its easier to simply fire of the hot wrench and tweak a steering arm than it is to sort through a variety of spacers and tapers. If you don't have access to an oxy/acetelyne set up to heat up an arm, spacers are an option.
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