Steering angle to me is the median of both tires angles, toe has to do with the difference between each tires angles. I guess you could use angle for single wheels but toe requires both wheels.
When you say Toe I think what you mean is Steering Angle. Those are 2 different things.
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Treefrog
Book Wheeler
Every suspension expect for a very limited number of special cases has bump steer. This includes full hydro solid axles and when the following the typical placement guidelines for double wishbone. The questions is how much bump steer and how it shows up.
Take TJ style Y steering, it has a change in the heading of the axle, toe change (driver's side), and uneven link arcs. A JK has uneven arcs and axle heading change. A full hydro axle only has the axle heading change. Double wishbone's show up as toe change.
It is possible to know that a car is going to have bumpsteer with a decent enough view of the suspension is shown. I won't comment on how much the bronco in question has since I couldn't find a good enough view, but based on some of the other things about that build I wouldn't be horribly surprised if it had quite a bit.
Take TJ style Y steering, it has a change in the heading of the axle, toe change (driver's side), and uneven link arcs. A JK has uneven arcs and axle heading change. A full hydro axle only has the axle heading change. Double wishbone's show up as toe change.
It is possible to know that a car is going to have bumpsteer with a decent enough view of the suspension is shown. I won't comment on how much the bronco in question has since I couldn't find a good enough view, but based on some of the other things about that build I wouldn't be horribly surprised if it had quite a bit.
arse_sidewards
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See also: Every stock TTB truck.
Treefrog
Book Wheeler
Funny thing is TTBs are one of the easiest ones to get 0 toe change on. Draw a line between the two frame points, put the frame steering point on that line. Other end goes anywhere. Doesn't mean 0 overall though.See also: Every stock TTB truck.
Too many people view steering as 2d projections instead of as a 3d puzzle.
Hey now, it's mostly just the drivers side. Does great turning left, right gets a little funny.See also: Every stock TTB truck.
arse_sidewards
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Treefrog
Book Wheeler
Eh. It's from the angling of the line. TTB and it's 2wd alternative are just the steering versions of the semi trailing arm desert cars run.
Lol what did I start.
First linked suspension I built would dive to the passenger side when ever I hit a speed bump. There is a lot of variables sure but putting the panhard on the same length/plane as the drag link got rid of it entirely. Can hit whoops and feels very stable now.
I was able to figure that out with a tape measure and a level, was not really that hard. You 100% can feel bumpsteer by hitting bumps.
First linked suspension I built would dive to the passenger side when ever I hit a speed bump. There is a lot of variables sure but putting the panhard on the same length/plane as the drag link got rid of it entirely. Can hit whoops and feels very stable now.
I was able to figure that out with a tape measure and a level, was not really that hard. You 100% can feel bumpsteer by hitting bumps.
arse_sidewards
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I'm well aware. They kinda got ****ed on packaging making it fit.
Drives me up the wall how many two bit yokels can't wrap their mind around the TTB being a singular A-arm on a line that just so happens to not be parallel with the chassis.
94 Ranger, 6' Skyjacker lift with 1" spacers under the coil and 4" drop pitman, hitting whoops at speed resulted in sawing the wheel back and forth like a drunken sailor to keep it going straight. Once I learned how to cope with it, it was fine, but **** whoever else drove that thing
definitely needed more pitman arm.
Rockwood
An Ape
In the context of the abomination above with a steering rack and A arms, it's toe change. In the typical IBB context, it's misalignment between the drag link and panhard, or just leaf spring ****. Bump steer can happen as a result of other things, but definitely happens when hitting bumps and is generally the first thing you should look at when the steering wheel wrenches out of your hands from a speedbump. Cycling the suspension and checking is just the easiest way to confirm you ****ed up as you build it, but that not as easy if it's already built...
Which is what my friends of almost 30 years in the video did: truck shows up, owner complains it's a handful. Friends drive the car, say "holy ****ing **** this thing is a handful," look underneath and see that the tie rods within 5% OAL of the LCA despite being 1/3 or more of the way up the knuckle, and say "yep, ****'s got bumpsteer." No need to take the coils off and measure how ****ty it is. It's really ****ing obvious that suspension needs to be completely redone. Same thing as any of us can look at this:
And know it's going to be a handful without measuring how much of a handful it is.
Subject at hand: I can assure you that Bronco does not have 0.01" of toe change.
Naw, A arm is self-supported (no trailing/radius arm) pivoting relatively perpendicular to the chassis. Self-supported in line with the chassis is trailing arm, somewhere in between is semi-trailing arm . TTB is, well, TTB. Other than whoop scissors, or swing arm (but not really), nothing really to call it. It's spashul.
Those very special cases probably chased bumpsteer at the cost of all else and likely handle or steer (or both) like ****.
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Rockwood
An Ape
Other than breaking as a result of over exuberant suspension travel, how does a solid axle have toe change...?
WaterH
Well-known member
I suppose if a solid axle is mounted on radius arms, they swine in an arc. As they arc, the toe would change unless it has zero toe. It wouldn’t be much though. I doubt you could even feel it.
Rockwood
An Ape
A solid axle is just that: a solid connection between the knuckles. The radius arms connect to the axle assembly and it all moves in an arc as an assembly. There should be zero change in toe due to suspension travel (bumpsteer) unless you're talking about super minor flex in joints...
Only measurable change in "toe" should be due to Ackerman, but that's not bumpsteer, nor is it how you measure toe. Something is breaking or broken if a solid axle has measurable bumpsteer due to suspension travel (bump/droop).
WaterH
Well-known member
I understand all that and I agree it would be negligible. I don’t think you follow what I’m saying.
If you have two tires that are exactly parallel, it doesn’t matter where they touch the ground, they will have the same toe. (That toe being zero) But if you have any plus or minus toe set, it matters where the tires touch the ground. Make sense?
Another way to explain. Let’s say you have 5 degrees of toe with the pinion level. If you spin the whole axle so the pinion is straight up, the toe effectively becomes camber and you have zero toe. Get it?
Obviously, the arc of a radius arm is not going to be anywhere close to swinging the pinion straight up, but you can’t say there’s no change in toe.
Rockwood
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arse_sidewards
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So what about those multi-piece Chrysler A-arms with the seperate tension strut?
What happens when you weld the radius arm to the beam? Inboard the radius arm bushing?
The geometry is a triangle regardless of where it is. Some people are just dumb and can't get that.
total newb
senior jerk ass
Like ujoints and "compound angle".
There is 1 angle.
There is 1 angle.
total newb
senior jerk ass
Solid axle doesnt change dimention, y link steering does, depening on the design, drasticaly.
Rockwood
An Ape
Dammit. Forgot about that one. That said: Y-link is ****ty and doesn't count.
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Rockwood
An Ape
No clue what Chrysler A-arm you're talking about. Generic would be control arm. A arm (AKA wishbone) is this:
But yeah, it's a triangle in the end. They do behave differently (especially shock angles) depending on type.
total newb
senior jerk ass
No clue what Chrysler A-arm you're talking about. Generic would be control arm. A arm (AKA wishbone) is this:
But yeah, it's a triangle in the end. They do behave differently (especially shock angles) depending on type.
subybaja
E. Spengler
What makes you think they haven't? The dudes in the video do have the Bronco in their garage... (the point would have been better if they took the time to show it on camera)
I asked him in the comments.
arse_sidewards
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Rockwood
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Ah, yeah. Those are control arms.
total newb
senior jerk ass
Co worker needed to fix a chair....
Winchested
IH Scout SSII
Welded up my leaf spring over the weekend... Got me 400km home.
Sluggy
If you can't tone it, tan it!
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I've done that before but I ended up welding the leaves together to help spread the load.Welded up my leaf spring over the weekend... Got me 400km home.
Winchested
IH Scout SSII
Problem now is not being able to find a stock scout II main leaf! IHPA Zaed suggests I move to 2" 2wd square body 56" leaf springs. But I need this junk back on the trail for end of June.
