Suspension TECH Including Brakes, Wheels and tires

          
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  #141  
Old 08-28-2025, 01:58 PM
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Positive caster pushes the wheel backwards in the wheel well. By the sound of it though it seems like the offset could use a tweak. I'm assuming this is a 0 offset wheel. Do they offer something that is around a +5? to get the wheel inset a little more?

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  #142  
Old 08-28-2025, 02:55 PM
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Positive caster pushes the wheel backwards in the wheel well. By the sound of it though it seems like the offset could use a tweak. I'm assuming this is a 0 offset wheel. Do they offer something that is around a +5? to get the wheel inset a little more?
Sounds like I may have a caster problem. The wheels have a 8mm offset.

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  #143  
Old 08-28-2025, 03:06 PM
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On a 9", that's a 1/3" towards the inside, usually 4" to the outside is the sweet spot.

You could always roll that area in if it starts marking contact.




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  #144  
Old 08-28-2025, 03:55 PM
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Sounds like I may have a caster problem. The wheels have a 8mm offset.
This has factory control arms correct? It's not usually possible to get as much caster out of factory arms that would cause this type of issue.

Is the passenger side wheel moved towards the front of the wheel opening at all?

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  #145  
Old 08-28-2025, 05:42 PM
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This has factory control arms correct? It's not usually possible to get as much caster out of factory arms that would cause this type of issue.

Is the passenger side wheel moved towards the front of the wheel opening at all?
Yes, factory control rms. For alignment shims, I have 2 thin shims on the front of each control arm. n the back there are 5 on the right and 6 on the left. All thin. The right side wheel is pretty much centered in the wheel well. The left side is closer to the back of the well. Is there any reason I can't just take out a shim on the left rear? Or will that throw my camber and toe in off?

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  #146  
Old 08-28-2025, 05:46 PM
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Removing shims will effect all of your alignment settings. Caster, Camber and Toe.

Please measure your wheel base for driver and passenger side. It would be normal to have the passenger side slightly less if there is a road crown alignment dialed in. If there's a somewhat significant difference, this could indicate some panel misalignment, or even an out of square subframe.

Although based on the number of shims you are suggesting, I would think there's a decent amount of positive caster and negative camber in the system.

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  #147  
Old 08-28-2025, 06:03 PM
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Correction to what I said above about my shims. I said they were thin but It looks like they're all actually 1/8".

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  #148  
Old 08-28-2025, 07:05 PM
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Removing shims will effect all of your alignment settings. Caster, Camber and Toe.

Please measure your wheel base for driver and passenger side. It would be normal to have the passenger side slightly less if there is a road crown alignment dialed in. If there's a somewhat significant difference, this could indicate some panel misalignment, or even an out of square subframe.

Although based on the number of shims you are suggesting, I would think there's a decent amount of positive caster and negative camber in the system.
My wheelbase on the right is 107 1/8" and 107 1//4" on the left. So it's slightly longer on the side that has the wheel sitting further back. Although that difference may be within my margin of error. Interestingly both are out of spec which is supposed to be 108".

The distance from my tire tread surface to the edge of the wheel well at the very bottom (rocker panel) is 2 1/2" on the left side and 2 3/4" on the right

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  #149  
Old 08-28-2025, 07:11 PM
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Okay so you’ve got .625” shim stack in there. I don’t know how long the 2nd gen upper arm is, but that could theoretically be something like 5-6 degrees of caster. That would absolutely move the wheel backwards a noticeable amount.

Aftermarket arms that achieve those rates of caster are typically combined with a lower control arm that moves the ball joint forward to keep the wheel centered.

It’s okay that your wheelbase is out of spec. Spec would be for a car with very little positive caster. And the difference side to side is within spec for what you’d see with a road crown alignment.

Now that the spacer has been removed do you have any contact?

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  #150  
Old 08-28-2025, 07:39 PM
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Okay so you’ve got .625” shim stack in there. I don’t know how long the 2nd gen upper arm is, but that could theoretically be something like 5-6 degrees of caster. That would absolutely move the wheel backwards a noticeable amount.

Aftermarket arms that achieve those rates of caster are typically combined with a lower control arm that moves the ball joint forward to keep the wheel centered.

It’s okay that your wheelbase is out of spec. Spec would be for a car with very little positive caster. And the difference side to side is within spec for what you’d see with a road crown alignment.

Now that the spacer has been removed do you have any contact?
No contact now without the spacer. That made a bigger difference than I thought it would. At it's worst, the tire get's about 1/8" clearance the fender bolt but no contact. With the spacer it was making contact with the fender.

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  #151  
Old 08-29-2025, 07:55 AM
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I'm guessing you did lock to lock checks too?



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  #152  
Old 08-29-2025, 07:56 AM
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Aftermarket arms make a huge difference by the way.


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  #153  
Old 08-29-2025, 10:18 AM
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I'm guessing you did lock to lock checks too?

Aftermarket arms make a huge difference by the way.
.
Yep, no contact at either extreme. And yes, I'm doing the whole suspension this spring. I'm pretty excited about that.

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  #154  
Old 08-29-2025, 10:41 AM
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If no contact currently, I'd leave it until you do the suspension. You'll need an alignment after that anyway.

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  #155  
Old 08-29-2025, 05:27 PM
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Looks great with the new wheels. A 2 1/2" drop front and rear would look pretty mean and would handle amazing

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  #156  
Old 08-29-2025, 06:09 PM
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Looks great with the new wheels. A 2 1/2" drop front and rear would look pretty mean and would handle amazing
2.5"? . I'll be scraping the pavement with sparks flying out behind me. But seriously, I'm going to keep the front stock height. Right now the back is too high. I think an inch, maybe 1.5" lower to give it the factory rear end squat. I know it may not handle quite as good, but it will look better (to me). In the famous words of Billy Crystal, "It's not how you feel, it's how you look." Or something close to that.

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  #157  
Old 08-29-2025, 06:15 PM
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You have replacement leafs on the back?


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Theme Song: http://www.youtube.com/watch?v=7zKAS...ature=youtu.be
  #158  
Old 08-29-2025, 06:25 PM
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You have replacement leafs on the back?


.
Yep. This will be the second time I'm doing the suspension. I replaced all the springs about 2 years ago because the car was too low. I need a better Crystal Ball.

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  #159  
Old 08-29-2025, 07:07 PM
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"It's better to look good than to feel good...you look marvelous!" - Billy Crystal

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  #160  
Old 08-29-2025, 07:42 PM
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You could have the leaf springs de-arched. I had this done to my 70 TA to drop the rear about an inch...It ended up exactly where I wanted it, so didn't have to play guessing games...also very inexpensive and didn't seem to affect ride or handling. See before and after pics.

As an aside, surprised how long this thread is getting...lots of good information though...maybe we need a pro-touring section?



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