Suspension Alignment specs

[7991LXnSHO]

Please post for me what stock and spirited driving front alignment specs should be for a 91 LX, 5.0, factory pony 5 spoke rims, B springs, BBK C/C plates.
I have had it with the closest tire place. They have a fancy machine and poor operators, and have made three vehicles pull or feel squirrely that did not before they checked and “fixed” the alignments. Multiple trips back change the problem changed the direction of the pulls, but did not fix it or the crooked steering wheels. So before I go elsewhere, I would like to be armed with the right numbers.
thanks!
@Warhorse Racing

 

[HemiRick]

toe out 1/16" caster all the way back, you want as much as possible, camber -1

 

[90sickfox]

You need to find a different shop.

 

[7991LXnSHO]

You need to find a different shop.

That’s what the plan is.

 

[Mustang5L5]

I go by what MM recommends in their caster/camber plate instructions.

SInce i DIY my own alignments, i tend to settle on MAX caster, 1/16" toe in, 0.5-1 degree camber

 

[Warhorse Racing]

There's a lot of good info here so far. When you start moving outside the factory alignment settings it's a good idea to find a shop that has experience doing "competition" alignments. Getting the right alignment is a bit of an art, so it takes a skilled tech.

A competition alignment can also have some issues under "normal" driving. My autocross cars tend to wander on roads with a crown. You want as much caster as you can get. If you are going to pay for another alignment, I would consider installing offset A-arm bushings (there are Poly and Delrin versions available). They will move the front wheels forward and allow for more caster. The Global West Del-A-Lum bushings I installed on my Fox made a noticeable difference in how the car felt on course. They are relatively cheap, but they do require a press to install.

The amount of negative camber depends on your willingness to wear out your tires faster than normal. For a daily driver solid rear axle Fox Body, I would say that -2 degrees is probably as far as most people would go. And you would want to rotate your tires more often. If you plan on racing the car, you would want more.

My autocross Fox is camber-limited due to the SN95 spindles, so I run -1.3 degrees. I'm not willing to cut the car up to get more, but ideally it would be set to -2.5 degrees. That car handles pretty well for not having a lot of negative camber.

All my autocross cars have 1/16" toe out.

Keep in mind, I don't daily drive my cars, and my tires only last 3,000 miles (not because of the alignment).

For a street car, I would personally go with max caster (with offset bushings), -1.5 degrees of camber, and 1/16" toe out.

 

[7991LXnSHO]

Toe out? Is that for quicker turn in? When I learned about alinement, toe in was make sure your tires were still straight with road forces on pre rack and pinion vehicles.

 

[7991LXnSHO]

@Warhorse Racing so besides toe out,
“My autocross Fox is camber-limited due to the SN95 spindles, so I run -1.3 degrees. I'm not willing to cut the car up to get more, but ideally it would be set to -2.5 degrees. That car handles pretty well for not having a lot of negative camber.”

I do not have the ‘95-6 spindles or bigger brakes in at this point. If I do, is there more to do besides loosening the strut to spindle bolts, moving them (in?) and tightening them up to get max camber?

 

[Warhorse Racing]

@Warhorse Racing so besides toe out,
“My autocross Fox is camber-limited due to the SN95 spindles, so I run -1.3 degrees. I'm not willing to cut the car up to get more, but ideally it would be set to -2.5 degrees. That car handles pretty well for not having a lot of negative camber.”

I do not have the ‘95-6 spindles or bigger brakes in at this point. If I do, is there more to do besides loosening the strut to spindle bolts, moving them (in?) and tightening them up to get max camber?

There are a few things you can do to compensate for the camber issue created by using 94-04 spindles. Keep in mind that there are some differences between 94-95 and 96-04 spindles. In order to get more negative camber you can:

Elongate one mounting hole in the strut so that the top of the spindle can move inboard. You can drill new holes in the strut tower to move the CC plates inboard. Or you can use longer SN95 A-arms.

 

[7991LXnSHO]

There are a few things you can do to compensate for the camber issue created by using 94-04 spindles. Keep in mind that there are some differences between 94-95 and 96-04 spindles. In order to get more negative camber you can:

Elongate one mounting hole in the strut so that the top of the spindle can move inboard. You can drill new holes in the strut tower to move the CC plates inboard. Or you can use longer SN95 A-arms.

Edit, I have 94-5 spindles I plan on using if I upgrade brakes. I have 96 spindles I plan on reselling. Both pair hurt to stub my toes on in the dark on the way to the garage fridge.

 

[Warhorse Racing]

Edit, I have 94-5 spindles I plan on using if I upgrade brakes. I have 96 spindles I plan on reselling. Both pair hurt to stub my toes on in the dark on the way to the garage fridge.

Planning for the spindle swap is important. MM has a really good resource: https://www.maximummotorsports.com/tech_front_susp_7993to9604_spindle.aspx

As you'll see in that guide, bump steer and camber issues come into play with the different spindles. I have 96-04 spindles on my Fox and I've never had a bump steer issue, but it's not lowered very much.

 

[7991LXnSHO]

I think (it might even have been before I joined here) I got the 96 spindles from someone who did not know the difference, and I saw the missing Z in the arm too late to send them back.
So anyway, why the toe out? I am thinking I want to have for toe in for stable highway driving, right or wrong?

 

[Warhorse Racing]

I think (it might even have been before I joined here) I got the 96 spindles from someone who did not know the difference, and I saw the missing Z in the arm too late to send them back.
So anyway, why the toe out? I am thinking I want to have for toe in for stable highway driving, right or wrong?

Toe out helps with turn-in for performance driving. If your car will see more highway use, you might prefer zero toe or a little toe in.

 

[Mustang5L5]

You control arms will also play a little role in deciding your toe settings. If you are using stock style control arms with rubber bushings, you want toe-in as the action of driving foward and the compliant bushings will cause the front wheels to toe out slightly (or be nuetral). With aftermarket bushings (poly, delrin) that effect is less so a more nuetral setting can be used (for a street car). If racing, toe out will make an improvement in turn-in, but I’ve found it to make a street car darty over crappy roads.

so you need to make a decision based on your usage of the car and your parts components.

 

[7991LXnSHO]

You control arms will also play a little role in deciding your toe settings. If you are using stock style control arms with rubber bushings, you want toe-in as the action of driving foward and the compliant bushings will cause the front wheels to toe out slightly (or be nuetral). With aftermarket bushings (poly, delrin) that effect is less so a more nuetral setting can be used (for a street car). If racing, toe out will make an improvement in turn-in, but I’ve found it to make a street car darty over crappy roads.

so you need to make a decision based on your usage of the car and your parts components.

Thanks for confirming that my knowledge was not out of date, and for providing the right specs for when I go to the shop. If they say they are going to align it to other specs, I will go to a different shop.