Chopped Pitman Arm
- Rawbert
- Sweptline.ORG Member
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Chopped Pitman Arm
After installing my dropped beam I had to deal with my bump steer problem. Choppin' the pitman are was the way to go. I have a 71' with power assist, so my arm has the bend. To keep the geometry aprox. the same minus the amount of throw, I built a jig to keep everything strait. I put a deep chamfer around everything and T.I.G. weld the crap outa it. Six passes around the whole thing, while letting completely cooling between passes. Strong as hell!. In the end I ended up moving the lower mounting hole up 1.750". Mounted up is just right. Drag link is now parallel to the ground. No more bump steer! Let the pictures do the talkin'.
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- Sweptline.ORG Member
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Re: Chopped Pitman Arm
thats about how i did mine too. did you pre/ post heat ?
- Rawbert
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Re: Chopped Pitman Arm
Just pre-heat. Let it cool for about 2 hours in between passes
- dodgeboykim
- Sweptline.ORG Pioneer
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Re: Chopped Pitman Arm
Some nice looking Tig passes.
- jwing68
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Re: Chopped Pitman Arm
Very nice welds, unfortunately it is highly illegal to chop and weld steering components in this neck of the woods.
66 Fargo W100 Sweptline SWB Poly 318
67 Fargo W100 Sweptline SWB Poly 318
68 Fargo W300 dually LA 318
66 Dodge W200 Poly
65 Dodge W300 dually Poly 318
68 Pontiac Firebird 350
2005 HD FXST Custom
67 Fargo W100 Sweptline SWB Poly 318
68 Fargo W300 dually LA 318
66 Dodge W200 Poly
65 Dodge W300 dually Poly 318
68 Pontiac Firebird 350
2005 HD FXST Custom
- Rawbert
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Re: Chopped Pitman Arm
Bummer... And I thought California was strict.
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- Sweptline.ORG Pioneer
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Re: Chopped Pitman Arm
Actually it's on the books here, but they don't inspect cars like they do up in the Great White North.Rawbert wrote:Bummer... And I thought California was strict.
- rmansberger
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Re: Chopped Pitman Arm
What is bump steer?
Rick
Rick
Rick Mansberger
1967 Mustang "Duke"
1970 Dodge D100 "The Dude"
1978 GMC Suburban "Big Cub"
2006 C300
2014 RAM Limited "Master Sergeant"
517.599.7667
1967 Mustang "Duke"
1970 Dodge D100 "The Dude"
1978 GMC Suburban "Big Cub"
2006 C300
2014 RAM Limited "Master Sergeant"
517.599.7667
- slick
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Re: Chopped Pitman Arm
Damn those are some nice welds..
1963 Crewcab Cummins
1961 Dodge D100
1964 Dodge Polara
1961 Dodge D100
1964 Dodge Polara
- Rawbert
- Sweptline.ORG Member
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Re: Chopped Pitman Arm
I don't know the technical definition of "bump steer" but it is like driving with little control. the front wheels pull when brakes are applied or when ever the wheels are not strait. When you counter steer to keep it strait it pulls that way. Kinda fun but extremely dangerous.
Re: Chopped Pitman Arm
Rick, the steering components tend to operate in arcs, while the suspension moves linearly. The steering geometry is set up so that when the components move, as much of the motion as possible is close to linear so that when you hit a bump, the wheels don't turn in a different direction due to the differences in motion. When you lower or raise the front suspension, you change the angles of components like the Pitman arm and the drag link so that their motion is in a slightly different direction when the suspension moves. It doesn't take much of a change - if the drag link isn't close to parallel to the ground or the Pitman arm isn't close to vertical, when you hit a bump, instead of the drag link just moving up and down, it will also move fore and aft a little, pulling the steering one way or another...or, if the tires stay straight, the wheel will jerk in your hands.rmansberger wrote:What is bump steer?
- 66patrick
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Re: Chopped Pitman Arm
http://en.wikipedia.org/wiki/Bump_steer
The link has a couple of good illustrations to bolster the definition.
The link has a couple of good illustrations to bolster the definition.
[b]Patrick - 1969 D300 cab & chassis[/b]
Re: Chopped Pitman Arm
I lowered my 66, used original springs and had them re-arced at spring shop. White knuckle driving!! From bump steer. I moved my steering box to in front of axle, using original draglink. Also made a bracket and raised it so drag link was running horizontal. Then took to alignment shop and had toe set. Installed 22" tires. drives straight, no bump steer fun to drive now.
Brucer
Brucer