The man wants MORE caster. How about this idea?

[Inertia]

I was going to ask "how much caster do you need"? Bacially enough for the car to drive down the road with no hands on the wheel. May be more for a drag car or one for the salt flats.

Factory settings were "0" to minus "1", ( think front wheel of shopping buggy flopping around) - so any pos caster is going to give better directional stability
I just don't get this wheel "slamming" back to center .
On a long race/drive, no power, that's fatiguing
Coast road without power steering, caster +6. lol.
I understand and use big caster for autocross, road course, ya know, racing, - but for street, absurd .
jmo

 

[BillGrissom]

Why do the aftermarket UCA's have different PN's for the 3 different spindles (9" or 10" drum, or disk), since factory UCA's were the same PN 1963-72?

I wouldn't cut and re-weld the factory UCA's since a lot of effort for no-bling. But, I wouldn't worry about safety when you compare to factory control arm failures in other cars (google). I reviewed that during an internet fuss by "experts" (never swung a wrench) over a temp fix I did to my 1984 M-B to drive it home, saying I could have killed people. I found many early 2000's M-B lower control arms failed by rusting thru from the inside (hollow tubes, unpainted inside). They look fine until they break apart. Ditto for many other cars. Usually happens at low speed in parking lots when turning sharp (highest loads). Even at speed, one can still steer with one wheel splayed out, and the car usually drags on the ground to brake the car, so rare to cause an injury or even damage to the vehicle. The UCA's in our cars see minor loads, and just orient the spindle. One aftermarket UCA for our cars has experienced weld failures, which is strange since it looked like a slick design with nice-bling.

 

[72bluNblu]

I'm curious at what point you think there is too much caster ?
There has to be a "too much caster", how much is that, and what is the symptom ?
When stuff never meant to take the stresses bend/flex and break, tire wear ?

Adding caster means you get additional camber when you turn the wheels, which does a few things. It makes it harder to turn, because you're basically lifting the car by putting the tires more on edge.

So from an effort standpoint, it gets harder and hard to change direction quickly. So there's definitely a point where you're going to be making it too difficult to turn, especially if you're not running power steering.

From a handling perspective though, the point is to keep the inside tire flat on the ground. If you add too much caster, you're going to be adding too much camber on the wheel when turning. So you could actually lose contact patch by putting the tire too much on edge. The other thing is, you are trying to lift the car when you put that much angle on the tire and that can have an unsettling effect when you're turning in, you can actually upset the balance of the car if you get too extreme.

Factory settings were "0" to minus "1", ( think front wheel of shopping buggy flopping around) - so any pos caster is going to give better directional stability
I just don't get this wheel "slamming" back to center .

Yeah but the factory settings were for bias ply tires, which have a built in recentering effect because of their construction. The moment you put radials on the car the factory settings are wrong.

On a long race/drive, no power, that's fatiguing
Coast road without power steering, caster +6. lol.
I understand and use big caster for autocross, road course, ya know, racing, - but for street, absurd .
jmo

View attachment 1716208223

Actually you're backward on this. For racing you'd want the caster to set up the right amount of camber on turn in. You don't necessarily need a ton of positive caster for autocross at all, because the speeds are slow and you're always turning one way or another. So high speed stability isn't a concern. Especially for slower speed tracks you'd probably want less caster than you'd want on the street if you were running manual steering and wide tires, as long as your camber gain was decent and you didn't have a ton of body roll angle.

On a road course you'd want a good amount of positive caster. The high speeds would require stability, and with wide sticky tires in the front you'd want to have the handle on them. It would still be a balance, because the higher speeds also make upsetting the balance of the car on turn in more likely.

On the street, or most streets anyway, you're actually doing a lot less turning than anything else. And lousy road quality increases the "tracking" and rut following kind of tendency you get with a wider front tire. And for freeway driving the high speed stability is definitely a thing, if you're running too little caster and tracking all over the road that's fatiguing too.

I'm always driving mountain roads now, pretty much anywhere I go. I run 275's with +6.5° of caster and 16:1 manual steering. My commute to work is over an hour of driving, and at least 45 minutes of it is fairly curvy mountain roads before I hit the freeway. The mountain roads aren't an issue at all for fatigue, and the steering on even my car doesn't start to get heavy until I drop under 20 mph. It may actually be a little high on the steering effort for a tight/slow autoX course, but on the street it's great for everything but parallel parking.

 

[Bryan Lohmiller]

View attachment 1716205582


I like that they have a pad for the upper bump stop and that the ball joint mount looks gusseted.

the ball joint mount might be gusseted but you still have the sane issue the ball joint screws in that's mopars week point. But with new ball joints in these might outlast the stock ones. I'm running these in my duster at my tire/alignment guys recommendation tubular uppers for more caster

 

[Inertia]

I just love the way Blu does that, I open a door, he bursts right in and fills the void with his tech and minutiae, then leaves supporting my point.
Big caster causes heavy steering in traffic and parking lots, which may be challenging for small folks who aren't expecting it .

You don't need a ton of caster to get directional stabilty .
Thnx Blu

 

[OLD IRON]

It also makes the car easy for the wind to blow around on the highway.

 

[Dan Georgino]

Okay, feel free to let me have it if you think that this is a bad idea but.....
To those that want their cars to handle better, aligning the car to have more caster really helps.
There are numerous ways to get there, some are more effective than others. You can crack open the wallet and buy aftermarket stuff. The Hotchkis stuff seems to be almost infinitely adjustable but holeeeee crap they are expensive.

View attachment 1716205568

Even the Firm Feel is spendy...

View attachment 1716205569

With the Firm feel, you're at the mercy of whatever added caster they engineer in. That is fine but still...$450?

FABO sponsor PST doesn't list one for the A body.
If you like your stock stamped steel arms, you're limited to using the Moog K-7103 offset bushings:

View attachment 1716205570


They do work, I have them in my '70 Charger. I must be blessed though because even with standard bushings, this car was able to get over 3 degrees of caster. Now with the bushings, I was able to get 5 degrees on one side, 5.5 on the other. This has to be a case of an absolute positive tolerance stack up!
Okay, back to the point. If you're always looking to do more with less and can weld....
How about this?
How about cutting the UCA on the forward leg, spread it 1/4" and welding in another section?

View attachment 1716205571

Properly welded, it wouldn't fail. The slight change in angle will affect the rear bushing slightly but not enough to matter. This can be done for next to nothing. The 1/4" piece sectioned in could come from small ball joint UCAs that are not as valuable to some people. By welding in an extension, you'd still be able to use any type of bushing, offset or stock so there would still be the same range of adjustment.
Opinions?

 

[72bluNblu]

I just love the way Blu does that, I open a door, he bursts right in and fills the void with his tech and minutiae, then leaves supporting my point.
Big caster causes heavy steering in traffic and parking lots, which may be challenging for small folks who aren't expecting it .

You don't need a ton of caster to get directional stabilty .
Thnx Blu

LOL. First, I really didn't support your point.

And you're still speaking in generalities, with no quantitative information given at all. What's "a ton" of caster, or "big" caster? Is that +5° you're talking about? or +10°? Absurd is running less than +3° on the street with radial tires, even skinny ones.

Yes, you can have "too much" positive caster. That's really obvious if you know what caster actually does.

Like almost EVERYTHING suspension related, how much caster you need/will want depends on how your car is set up and how you're using it.

The +6.5° I run on my Duster isn't too much. I've run my Duster with 275's up front with everything from about +3.5° of caster all the way up to +8° of caster, and +6.5° is great, even with my 16:1 steering. I suspect you're trying to suggest that's too much, but that's wrongheaded. Of course parking lot speeds mean heavy steering, but most people would consider a 16:1 manual steering box with ANY amount of caster "heavy" at parking lot speeds. With the way my car is set up, once you start dropping below about +6° of caster the tracking effect from the wide front tires starts to become noticeable. And really after you drop below around +5° or so even the reduction in steering effort from dropping more caster is less noticeable too. Above about +7° and the steering effort starts increasing exponentially, and the "jacking" effect you get from turning the wheels becomes more noticeable.

But it depends on your set up, @BergmanAutoCraft was running his Dart with +7.5° of caster the last I saw him post his specs. But he's running Borgeson power steering, so the added effort isn't an issue.
Hotchkis or QA1 all inclusive kits - which one?

And I've had no issues with tire wear, breakage, etc. running +6.5° of caster. Even running -1° of camber, which is more of a tire wearing setting anyway.

View attachment 1716208480

The thing about the SKOSH chart is you have to remember is how old it is- it's well over 30 years old. It's basically a guide for the kind of all season radials that are popular on 15" rims, and the 15" rim itself is pretty limiting on how wide a tire you can run. The other thing is that offset UCA bushings with stock UCA's were really all most people had access to when the SKOSH came out, so getting more than +4° of caster wasn't easy to do. And even the SKOSH recommended more caster for the FMJ cars, and some of us run FMJ spindles for their additional camber gain.

With adjustable UCA's out there, and 18" rims that allow you to run 275's up front with soft, high performance tires, the SKOSH chart is pretty conservative for positive caster. I wouldn't run less than +5° if I was going to run 255 or wider front tires on the street, and that's more than the SKOSH recommends for track/autoX use.

Most modern high performance cars run +9° of caster or more, that's the spec for an SRT Challenger for example. But they're all power steering.

Still, for more modern tires I'd add +1.5° of caster to every category on the SKOSH chart, even for manual steering.

 

[Kern Dog]

View attachment 1716208480

Yeah, thanks for that. I am well aware of it and have seen it numerous times.
Some may have not so posting it may allow them to copy and paste it to their files for future use.
72Blu was right in that it IS a really old chart that does apply in most cases with most people but doesn't take into account power or manual steering.
I have over 5 degrees of caster with stock UCAs and offset bushings. Some people like 72 Blu have even more and love it.
The point of this thread was to explore a low cost way to increase the caster to well beyond the "skosh chart".

 

[Dan Georgino]

Yeah, thanks for that. I am well aware of it and have seen it numerous times.
Some may have not so posting it may allow them to copy and paste it to their files for future use.
72Blu was right in that it IS a really old chart that does apply in most cases with most people but doesn't take into account power or manual steering.
I have over 5 degrees of caster with stock UCAs and offset bushings. Some people like 72 Blu have even more and love it.
The point of this thread was to explore a low cost way to increase the caster to well beyond the "skosh chart".

Doesn't that much Caster put a big stress on the control arm?

 

[Inertia]

I just gotta throw this out there, I think I know, lol

Where/how do you measure toe-in @ 6+* caster ?

 

[Kern Dog]

Doesn't that much Caster put a big stress on the control arm?

I don't know. If it does, where would it show? Do you think it would result in a premature failure? If so, at which point? Early bushing wear? Cracks in the UCA somewhere? I've had neither.
The car steers great, it tracks straight and is extremely stable at any speed. There is no irregular tire wear. I call that a win.

 

[Dale Davies]

As a professional welder, I like the idea BUT welding changes the metal. It will be harder in some areas and softer in others.
With that said, dependent on what you weld could effect the torsional twist all control arms face going up and down and shifting body roll. It’s why those expensive control area are expensive. The tubing and gussets are far superior to the factory arms flexing in the case of a road course. Or hard Sunday driving. Sadly most people welds are not up to The welding needed to accomplish your fix. Will this work- absolutely. Will it last?…. I’ve seen a lot of welds in my 54 years and most I would not walk on 1 ft above the ground let alone 50ft up. (inside saying with most professional welders. Would you trust somebody’s welds 50ft off the ground to walk on.)
Syleng1

Post weld stess reliemf and heat treatment. If going this route, I w.ould box the contol arm before stress telief and heat treat.

 

[Dale Davies]

I just gotta throw this out there, I think I know, lol

Where/how do you measure toe-in @ 6+* caster ?

Ca.mber, caster and toe are separate setting. Adjusting one can make a change on the others.
Toe if doing it by string line method is measured at the centers of the front wheels with the steering box centered and the wheels pointed to drive straight ahead.
On my 1940 Ford with Mustang 2 front suspension, someone screwed an alligator and the rack is not centered. The signal cancel does not work evenly left and right. Align.ent shops have not caught this as the steering wheel was installed to the center position. It may be the intermediate shaft installation that is
wrong.

 

[toolmanmike]

Ca.mber, caster and toe are separate setting. Adjusting one can make a change on the others.
Toe if doing it by string line method is measured at the centers of the front wheels with the steering box centered and the wheels pointed to drive straight ahead.
On my 1940 Ford with Mustang 2 front suspension, someone screwed an alligator and the rack is not centered. The signal cancel does not work evenly left and right. Align.ent shops have not caught this as the steering wheel was installed to the center position. It may be the intermediate shaft installation that is
wrong.

Center the rack turn to turn and set the toe to straight ahead. It will need to be done on a machine. It was installed a turn off I bet.

 

[autoxcuda]

Doesn't that much Caster put a big stress on the control arm?

No.

Not in a double wishbone suspension design with upper and lower ball joints.

 

[Dale Davies]

Center the rack turn to turn and set the toe to straight ahead. It will need to be done on a machine. It was installed a turn off I bet.

About 1/3 to 1/2 turn out. I have the engine out and want to redo the ugly engine mounts that wdre welded over the Ford serial stamping location. To fix stoopid you sometimes have to go back to beginnings.

 

[Inertia]

Ca.mber, caster and toe are separate setting. Adjusting one can make a change on the others.
Toe if doing it by string line method is measured at the centers of the front wheels with the steering box centered and the wheels pointed to drive straight ahead.

Shouldn't toe be taken at 90* to the kingpin, thus +6(?)* Off horizontal, - up in the fenderwell front, - down on the ground behind the wheel ?

 

[Dan Georgino]

Shouldn't toe be taken at 90* to the kingpin, thus +6(?)* Off horizontal, - up in the fenderwell front, - down on the ground behind the wheel ?

If you measure behind the wheel, then it's +1/8 or 1/4 or 0 or you'll be pigeon toed. Lol

 

[autoxcuda]

Shouldn't toe be taken at 90* to the kingpin, thus +6(?)* Off horizontal, - up in the fenderwell front, - down on the ground behind the wheel ?

No.

Toe is relative to driving surface (ground/horizontal).

 

[72bluNblu]

Doesn't that much Caster put a big stress on the control arm?

You have to think in terms of supporting the weight of the car.

Sure, adding 6+ degrees of positive caster increases the steering effort. But the amount of force you need to add to notice a change in the steering effort is fairly small, especially when you consider that the control arms are carrying the weight of the car (especially the lower one). So adding 10 lbs of resistance to the steering effort might seem like a big deal when you're trying to turn the steering wheel, but for the suspension that's carrying say, 800 lbs on one of the front corners? Not significant at all.

I just gotta throw this out there, I think I know, lol

Where/how do you measure toe-in @ 6+* caster ?

The same place you always measure it, on every car, regardless of how much caster it does or doesn't have. Doesn't matter if the caster is -1° or +10°.

Shouldn't toe be taken at 90* to the kingpin, thus +6(?)* Off horizontal, - up in the fenderwell front, - down on the ground behind the wheel ?

Nope. The toe measurement is independent of pretty much everything regarding suspension geometry. If you're measuring it yourself, it's just the difference in the distance between the front tires taken at the front of the contact patch and the rear of the contact patch.

If you're measuring it on an alignment rack, it's just the angle the wheel makes from the longitudinal axis of the car.

Adjusting the caster and camber will change the toe, but, they don't have anything to do with actually measuring it for a static alignment.

 

[Bodyperson]

You have to think in terms of supporting the weight of the car.

Sure, adding 6+ degrees of positive caster increases the steering effort. But the amount of force you need to add to notice a change in the steering effort is fairly small, especially when you consider that the control arms are carrying the weight of the car (especially the lower one). So adding 10 lbs of resistance to the steering effort might seem like a big deal when you're trying to turn the steering wheel, but for the suspension that's carrying say, 800 lbs on one of the front corners? Not significant at all.



The same place you always measure it, on every car, regardless of how much caster it does or doesn't have. Doesn't matter if the caster is -1° or +10°.



Nope. The toe measurement is independent of pretty much everything regarding suspension geometry. If you're measuring it yourself, it's just the difference in the distance between the front tires taken at the front of the contact patch and the rear of the contact patch.

If you're measuring it on an alignment rack, it's just the angle the wheel makes from the longitudinal axis of the car.



View attachment 1716208945

Adjusting the caster and camber will change the toe, but, they don't have anything to do with actually measuring it for a static alignment.

Individual toe should be measured at spindle height. This eliminates any difference in camber from side to side.

 

[Inertia]

No.

Toe is relative to driving surface (ground/horizontal).

Individual toe should be measured at spindle height. This eliminates any difference in camber from side to side.

If you measure behind the wheel, then it's +1/8 or 1/4 or 0 or you'll be pigeon toed. Lol

No.

Toe is relative to driving surface (ground/horizontal).

This is what I was suggesting with big caster .
Toe in will kinda be arbitrary, depending on where on the tire you measure the toe .
1/2 way up the wheel, -
90* from a kingpin, at the spindle, or the tire contact area.

Just promoting thought .
Thnx

 

[72bluNblu]

Individual toe should be measured at spindle height. This eliminates any difference in camber from side to side.

This is what I was suggesting with big caster .
Toe in will kinda be arbitrary, depending on where on the tire you measure the toe .
1/2 way up the wheel, -
90* from a kingpin, at the spindle, or the tire contact area.

Just promoting thought .
Thnx

Historically toe is measured at the contact patch. And that makes sense, because it's a tire wearing angle. And the tires wear at the contact patch don't they?

The other thing is, it is a difference. So as long as you measure at the same place on each side, the camber angle is taken out of it completely (if they're the same side to side).

Realistically, the camber should be very similar from one side to the other. As in within a degree. So, even if there was a slight difference in camber from one side to the other, the effect on the toe would be VERY minor.

 

[Bodyperson]

Historically toe is measured at the contact patch. And that makes sense, because it's a tire wearing angle. And the tires wear at the contact patch don't they?

The other thing is, it is a difference. So as long as you measure at the same place on each side, the camber angle is taken out of it completely (if they're the same side to side).

Realistically, the camber should be very similar from one side to the other. As in within a degree. So, even if there was a slight difference in camber from one side to the other, the effect on the toe would be VERY minor.

I "think" I am agreeing with you but measuring from a "rack" I'm thinking you are talking about computerized equipment. That is how computerized equipment do it. Not to mention set-back. How could we ever take that into consideration. I guess there is some trigonometry involved there. Without taking set-back into consideration, we end up setting toe equal to set-back.