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Discussion Starter #1
When I installed my SoT coil over front suspension I did my own alignment using a laser level, magnetic angle finder, a couple of framing squares and a 2x4 to set the toe. My job for 6 months 40 years ago was doing automotive alignments and my current job as a lot to do with angles. I think I'm at -1.5º camber, maybe 3.5º+ caster, with a 1/16" toe in. Shaun's general guidelines for road course alignment are -1.75 to -2.75 camber, +4 to +6 caster, and 1/32" to 1/8" toe in. He doesn't list autocross because maybe that's not his thing.

Given the current situation I can go into the dealership that my buddy Nick works at and we can monkey with the alignment on my Mustang all day for $100. No setting cross weights but it's still a pretty advanced machine. What should I be looking for? I'm thinking -2.75 camber and +6 on the caster. I think I'll have to bring my air saw for the front bottom edge of the front fenders to get anywhere near the +6 on the caster.

What are you running, or wish you were running alignment wise on a trailered car?

750292
 

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Spammer Hammer
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I could only go +3.5 caster with the Goodyear Blue Streaks. +6 is ALOT. I’d be surprised if you actually need that much. Caster just helps the steering return to center. If you aren’t having trouble getting it back to center I would go with what you can get without rubbing. There is a very slight tweak you can do to the bottom leading edge of the front wheel opening that a lot of road race guys do to get more clearance for the Blue Streaks. Mark pointed it out to me last year.
 

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Discussion Starter #3
I could only go +3.5 caster with the Goodyear Blue Streaks. +6 is ALOT. I’d be surprised if you actually need that much. Caster just helps the steering return to center. If you aren’t having trouble getting it back to center I would go with what you can get without rubbing. There is a very slight tweak you can do to the bottom leading edge of the front wheel opening that a lot of road race guys do to get more clearance for the Blue Streaks. Mark pointed it out to me last year.
We can only get what the car will give us caster wise. I'm running puny 225/45R/17's at this point and only have a 1/4" to the front lower flange on the front fender. I'm in the same but opposite world you are in running Cam-T. At this point 19" rims will get me inboard enough to not have to flare the front fenders excessively. Out back, I've got to go 3 or 4 link with mini tubs to gain enough meat to get somewhat competitive . I probably should just try to have fun with what I have!
 

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caster helps with more than return to center, it adds dynamic camber too.

I don't recall how much I have, but it's around 6 degrees as I used the +3 upper arms from global west and the SorT strut rods. Guessing Shauns upper arms have caster adjustment too...

Pretty sure I have something over -3 camber and zero toe.

probably should check it again soon to make sure it hasn't moved much haha
 

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Discussion Starter #6
I would try some toe out for autox speeds. It really helps turn in! I’ve tried up to 1/8” toe out on big tracks and the car almost turns itself. It gets spooky going straight above 100mph though.


Mark
Thanks, I've been wondering about that. I was thinking of starting at zero on the toe. Maybe I'll start a little toe out. I said to myself just yesterday how I don't like the way the hood shakes at 100 anyway!
 

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Ditto on toe out. It gives you more Ackerman.
 

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Agree with Mark. Two different animals, but when I auto crossed my ‘83 GT, I ran 1/8” toe out. When I changed to open track in the same car I changed it back to 1/8” toe in.
 

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We can only get what the car will give us caster wise. I'm running puny 225/45R/17's at this point and only have a 1/4" to the front lower flange on the front fender. I'm in the same but opposite world you are in running Cam-T. At this point 19" rims will get me inboard enough to not have to flare the front fenders excessively. Out back, I've got to go 3 or 4 link with mini tubs to gain enough meat to get somewhat competitive . I probably should just try to have fun with what I have!
How are you adjusting your caster? I'm assuming you've adjusted the heims on the upper arms? Doesn't that help move the wheel away from the lower front of the fender?
 

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Discussion Starter #10
How are you adjusting your caster? I'm assuming you've adjusted the heims on the upper arms? Doesn't that help move the wheel away from the lower front of the fender?
The heim joints are set at +2 and are as short as I could get them for tire clearance. I have to add shims to the front of the UCA or shorten the strut rod to gain more caster.
 

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I'd start by following the track alignment for autox. As much caster as you can get. I have +5 on my '66 and +7 on the '70!

Use the strut rods for fine tweaks, make most of your caster changes by the upper arm. Either adjust the length of the heim joints or shim the shaft or a combination of both. Using the strut rod for big changes pulls the wheel forwards in the wheel arch and you could end up with interference to the front valance. Aim to keep the LCA as perpendicular to the vehicle center line as possible.

I'd watch your tire wear for input on camber adjustments. If you are consistently roasting/feathering the outside edge then you likely need more static camber.

Its going to be challenging to get things perfect if the course layout and site of the autox always change. Keep a log book of vehicle specs at the time of the event and tires/pressures used. After a while you'll find out what does and doesn't work. Then you'll have the task of figuring it all out again when you change things on the car! :)
 

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Discussion Starter #13
I'd start by following the track alignment for autox. As much caster as you can get. I have +5 on my '66 and +7 on the '70!

Use the strut rods for fine tweaks, make most of your caster changes by the upper arm. Either adjust the length of the heim joints or shim the shaft or a combination of both. Using the strut rod for big changes pulls the wheel forwards in the wheel arch and you could end up with interference to the front valance. Aim to keep the LCA as perpendicular to the vehicle center line as possible.

I'd watch your tire wear for input on camber adjustments. If you are consistently roasting/feathering the outside edge then you likely need more static camber.

Its going to be challenging to get things perfect if the course layout and site of the autox always change. Keep a log book of vehicle specs at the time of the event and tires/pressures used. After a while you'll find out what does and doesn't work. Then you'll have the task of figuring it all out again when you change things on the car! :)
Thanks for the reply Shaun. I can't move the lower strut rods much before I hit the front of the fender well as it is. Shimming the front of the UCA out leads to the tire hitting on top of the fender. I plan on changing the shims on the LCA out to get -3 on camber because I am roasting the outside edges of the tires. That should move the top of the tire back behind the fender lip. It all sounds great in theory. It will be interesting how my 30 year old friend Nick reacts to the classic type of alignment. He has only turned a cam bolt and tightened in his career.
 

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My alignment is close to what you mentioned +3.5ish caster -1.5ish camber 1/8 toein I already trimmed the bottom front of my fenders.
I do a lot of street driving so I'm keeping the Toe as is ,as I feel it wears the tires less and is less darty on the street.
If your wheels are 17x8x4.75 you could try 255/40/17
 

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Ok...sorry in advance, I didn't read all the posts so not sure if you're running an adjustable camber kit. I'm running full SoT up front on my 66. My set up for autocross is 3 degree camber, 5 degrees caster, 1/16 toe out. Great even wear. 235/45/17 on all corners.
 

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Btw, how do you like the coilover? I was talking to Shaun and just couldn't cover the upgrade expense after buying tires. Feel real bad. The last thing I want is an outperforming front suspension to my rear suspension. If I do go coilover, I'd commit to doin an upgrade to the rear also. Is the performance upgrade worth the cost?
 

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caster helps with more than return to center, it adds dynamic camber too.
X2
Caster adds negative camber to the outside tire, which offsets the positive camber created by KPI. Is also affects weight jacking or dynamic wedge with steering angle. IIRC more caster improves turn-in ?
 

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Discussion Starter #18
My alignment is close to what you mentioned +3.5ish caster -1.5ish camber 1/8 toein I already trimmed the bottom front of my fenders.
I do a lot of street driving so I'm keeping the Toe as is ,as I feel it wears the tires less and is less darty on the street.
If your wheels are 17x8x4.75 you could try 255/40/17
Yeah dartyness is what worries me on the street with toe out, but hopefully I won’t be driving on the street much longer. 17x8 4.81 BS with 225/45 tires will have to make it through this season if there is one. I’m thinking it’s time to consider a tasteful flare on the fenders.
 

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Your title asked for auto cross alignment, but since you're concerned about street handling manners you'll need to determine which has priority and find a happy medium.
 

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Discussion Starter #20
Your title asked for auto cross alignment, but since you're concerned about street handling manners you'll need to determine which has priority and find a happy medium.
I’m trying to have a little fun on the street until autocross resumes. Darting and ditches don’t go together!
 
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