Following the SKOSH chart - your experiences?

MRGTX

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This guide seems to be generally accepted by folks on the forum.

What was the intent for setting up your car? How did you decide where you wanted to fall in these ranges? Did you go back and change anything after deciding that you didn’t like the performance/feel/tire wear?

Folks with 16:1 manual steering and some decent rubber on the front end- how much caster was tolerable?

What benefit would you gain from running toe-in (or toe-out per the "**")

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Demonracer

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Those are just general guide lines, your results may vary. And yes, you may have to go back & have the settings changed if it doesn't work out as you want it to.
 
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Jim Lusk

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I aim for something in the range of the street specs...With radial tires that is fairly necessary to drive right.
 

89on35s

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I set mine up as max performance street or as close as I could get. It wore out the front tires in a year. I went to typical performance street and I am on my second year with the same front tires and no visible wear. The tires have now are narrower if that makes a difference.

Cley
 

MRGTX

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I set mine up as max performance street or as close as I could get. It wore out the front tires in a year. I went to typical performance street and I am on my second year with the same front tires and no visible wear. The tires have now are narrower if that makes a difference.

Cley

how does the driving experience compare between the alignment specs?
 

89on35s

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No noticable difference honestly. However I don't have proper tires for a comparison of hard cornering.

Cley
 

MRGTX

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Well, 5* of caster, -1.5 camber and this car drives like a new machine!

as many have mentioned, the front bottom corner of the fenders is a now slight clearance issue at the mid point of steering travel, thanks to the extra caster and my particular wheel offset/tire combo.

I believe that the old rubber mallet and block of wood should be able to help without too much trouble.

CAC59FCC-97D0-4A81-8203-78EF8C8C923B.jpeg
 

GMachineDartGT

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Alignment specs depend on a lot of factors. If you use FMJ spindles for example, they have more camber gain in compression. This would allow you to use less static camber.
Caster is a big point of contention, as you increase caster, you are lifting the inside wheel in turns. There is a point where it becomes excessive. The Mopar manual calls out a max of 5 if I remember.
Toe can vary too as more toe can be used with the use of rubber strut rod bushings. I little less with heim jointed types as your toe change under load changes a little less.
 

MRGTX

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Before I do anything drastic, can anyone share how they reshaped that corner of the fender to accommodate the extra caster?

F8DEC81B-D501-4ABD-A5FA-6F1A2335781C.jpeg
 

72bluNblu

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Before I do anything drastic, can anyone share how they reshaped that corner of the fender to accommodate the extra caster?

View attachment 1715542251

If you haven't already maxed out the adjustment on the lower fender to bumper brace you can do that. On my car with my 275/35/18's I reshaped the corner (cut it off) and then extended the fender to bumper brace by a bit under 2". That pushes the lower corner out and away from the interference. It's actually not a super obvious modification, I stopped pushing right about where the fender started resisting the change and bowing out a little. If you sit it next to a stock car the difference in noticeable, but without a stock comparison it's fairly subtle.

This shows the brace and the corner modification
img_3544_zpsvnqc8dk8-jpg-jpg-jpg.jpg

Length change on the brace
img_1950-jpg-jpg-jpg.jpg


As for the rest, I run -1° of camber, +6.5° of caster, and about 1/16" toe in with 275/35/18's up front and a 16:1 manual steering box. I do see a little bit of camber wear on the inside edges of my tires. It's not so severe that it will scrap my tires before they need to be replaced for overall wear though. The steering effort on my car is fine IMHO at any speed over about 15-20mph. It is not a fun car to parallel park, but it is my daily driver with those specs. I have run everything from +5° to +8° of caster on it, I think +6.5° is pretty close to where I want it. More than that and the steering gets infinitely more difficult with even small increases in caster, less than that and I start to notice the tendency of those wide 275's to seek out ruts and low spots in the lanes. At around +6° caster the steering starts becoming a lot more stable, the car runs a nice straight line without any input. But that has a lot to do with the 275's up front, with narrower tires I think the happy medium for the caster would be lower.

With -1.5° camber you will definitely see camber wear on the tires unless you're always cornering with some lateral force. Between my Duster and my Challenger I've found that around -1° is where the camber wear starts to happen, below that it's not an issue at all, above that it becomes increasing more obvious. It will depend on your driving style and the use of the car, but for me anyway at -1.5° the tires would probably have to be replaced because of camber wear alone before the overall wear required their replacement.
 

MRGTX

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So I maxed out the adjustment on the fender brace and I tapped back some of the “excess” sheet metal on the inside of the wheel arch and it just barely clears! Thanks @72bluNblu. I may end up trimming and making a longer rod when I go to “real” tires some time in the future.

I’ll just say it again, the car drives so darned good now...my eyeball garage alignment allowed the car to track straight but I didn’t imagine how much it dampened the feel and dynamics of the car.

A performance alignment is worth its weight in gold. Just find a shop that won’t mind if you hang around while they make adjustments and be prepared for the process to take a while. The grease monkeys who did my alignment turned out to be a nice bunch of kids who were enthralled by the Dart. They took pictures, asked questions, etc. it was a good experience all around.
 

Demonracer

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MRGTX, I really liked the picture of the BFH. Sometimes it is so tempting for me to drag one out to adjust things when it's not going my way. Just as a side note, I used the drag racing specs for my Demon & it made a world of difference both going down the track, & in the shut down area after a mid 10 second pass.
 

autoxcuda

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This was pretty aggressive. Probably more than I needed right then

I was changing from:
Tires: 245/50/15
Rims 15x8
Backspace: 4 1/2”

To:
Tires: 245/50/15
Rims 15x9
Backspace: 4 1/8”

But planning to put 18x9 rims with 275/35/18 tires or something a little wider

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upload_2020-6-11_10-48-15.jpeg


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72bluNblu

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This was pretty aggressive. Probably more than I needed right then

I was changing from:
Tires: 245/50/15
Rims 15x8
Backspace: 4 1/2”

To:
Tires: 245/50/15
Rims 15x9
Backspace: 4 1/8”

But planning to put 18x9 rims with 275/35/18 tires or something a little wider

View attachment 1715544344

View attachment 1715544345

View attachment 1715544346

View attachment 1715544347

View attachment 1715544348

View attachment 1715544349

It would be aggressive for a Duster, Demon or Dart. But for a Barracuda it’s pretty much necessary any time you get up past ~25.6” for a tire height with any kind of width.

Barracuda’s have a tighter clearance to that lower front corner than any of the other A-bodies because of the shape/size of the front wheel opening.
 

Cruisingram

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Once I get it all together, I am going to align this thing, I think I am going to start with the typical performance street.
 

LO23M8B

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I didn’t have to cut anything. Just used a longer upper control arm, correcting the bump steer and put in some more caster and tons of room. Handles great you can let go of the steering wheel down the track and if you know how to drive/park it, it’s no problem at all.
 

Kern Dog

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I set mine up as max performance street or as close as I could get. It wore out the front tires in a year.

Cley
Toe settings will wear tires faster than negative camber will.
I have ran 3/4 to 1 degree of negative camber in my '70 Charger for 20 years and the tire wear is even...


01 Ginger.JPG
 
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