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joestang
03-15-2015, 10:02 PM
Hey Everyone.

I did a little searching the internet and this forum without success to my exact question. I could of missed it, but I figured I'll ask the experts!

A foxbody guy in Colorado needing some recommendations for setting bumpsteer. My first time doing all the alignment in my garage and could use some help.
I made all my own gauges to do the set-up since I'm too cheap to buy all the fancy tools from MM or elsewhere. Also I find it fun!
I've already done caster (checked camber at +20/-20 wheel turned) done camber ($10 level and bolts plus trigonometry) done toe (string around the car). And now on to bumpsteer...

The Car;
'88 Mustang, with SN95 control arms/spindles. Still using Fox steering rack and QA1 bumpsteer kit.

I've read a rule of thumb is to have less than .02" of toe change per inch of suspension travel, but toe change in what direction???

1. Should I have the toe travel go towards toe-in or toe-out during suspension compression?
2. Should I have the toe travel go towards toe-in or toe-out during suspension drop?

Overall I' going to try to shim the rod end to minimize toe travel but just don't know which way to bias the set-up.

Thanks for the help!

-Joe
CMC #21

joestang
03-15-2015, 10:36 PM
By the way, I'm a Rocky Mountain CMC guy, but I posted up here since I know the Texas guys have a good handle on the Foxbody cars and Mustangs in general!

marshall_mosty
03-16-2015, 09:45 AM
You will want to split the difference on bump and droop and shim to get the least amount of total change.

mach1
03-16-2015, 10:29 AM
This has been on my todo list, when I installed my BS kit I ran the a-arm through it's travel motion (simulated loaded) and shimmed until the tie rod angle and the control arm pivot point angles were as parallel as possible.
I have had no noticeable bumpsteer so it's been on my todo list for quite some time.

joestang
03-16-2015, 01:38 PM
You will want to split the difference on bump and droop and shim to get the least amount of total change.

Sounds Good.
I think I'll just try to make both sides act the same.
Thanks for the help.

Supercharged111
03-16-2015, 10:55 PM
So you're actually going to race this year? More cars, more better!