alignment check

[wile coyote]

V6 conversion coming along well. Replaced tie rods yesterday. Attempted to make new rods exactly the same link as the previous. I understand the toe-in is 1/8". Where is this measured? Doesn't it depend on the distance from the spindle where this is measured? I initially assumed this is measured at the tire centerline, but wouldn't that change with different size tires?

 

[Barry]

wile,

Toe-in is the difference between the tire-center line-to-tire-center line measurement at the front and back of the tires. You are correct about the toe-in measurement being related to tire diameter, but tires on Series Alpines are probably between 23 and 25 inches, so the difference is negligible.

 

[Charles Johns]

Guys, as I understand "toe-in" it is how far from the centerline of the front tire rolling-line (path) its front inward cant is from that rolling-path. If 1/8" is toe-in then the front of the tire is 1/8" closer to the car centerline than the center at the axle (spindle). Is it half per side? After 50 years setting toe-in, I learned on some YES and others NO. HAVE FUN. To further screw things up...the right tire should in theory have more toe-in due to it riding farther down the crown-of-the-road. I have a spring-loaded aluminum 2-piece rod that stretches between the front tires. With them pointing straight I measure the tread width at the tire/road contact. I then roll the car back until the rod is centered with the wheel center. The difference is total toe-in, or half that per tire. Are we having fun yet?

 

[wile coyote]

Well now that I have it running, the steering feels the same as before the engine swap. That being said, at about 70mph, it feels a little loose on swaying back and forth. I'm still trying to figure out how to measure to 1/8" accuracy without a straight shot from one wheel to the other on the leading edge of the tire.

 

[260Alpine]

With car straight, measure from floor to 12" up on outer front rim edge and mark. Do the same on outer rear edge. Use a string line or long straight edge along rim edge lined up with marks. Measure between both front outside and both rear outside of tread edge. Should be 1/8" wider in rear. Jackup and look for slop in all steering components. Tie rod ends, center link pivots and ends. Maybe even slop in steering box.

 

[PROCRAFT]

With car straight, measure from floor to 12" up on outer front rim edge and mark. Do the same on outer rear edge. Use a string line or long straight edge along rim edge lined up with marks. Measure between both front outside and both rear outside of tread edge. Should be 1/8" wider in rear. Jackup and look for slop in all steering components. Tie rod ends, center link pivots and ends. Maybe even slop in steering box.

Stretch a string from front to rear on the wheel centerlines, measure from the edges of the rims to get the string parallel from front to rear, take a measure ment from the front edge and then the rear edge of the front wheel a longer measurement at the rear edge will mean you have toe out and a shorter will mean toe in, this method I describe is still used by a lot of stuff today probably Vintage racers, however most have fixed place on the car( determined from the centerline ) for a set of "string bars" that are used to set the toe we've always used this method make sure the string is taut fixed on either end like maybe jack stands and use fish line its thinner. this should be done at the ride height your going to run we have actually done all our alignment in the air with the shocks removed and replaced with bar that are at the ride height were going to run, we set things like caster camber with a digital protractor.
one last thing the steering should be centered!

 

[Charles Johns]

It has been my experience that high-speed drifting is more a factor of not enough positive caster rather than toe-in. I always dial in a degree or two of extra positive caster in a car built for the highway. Light weight T-Buckets have this problem at high speed and they are nose heavy. Guys worried if the added caster would cause hard steering. NO, the cars were so light a degree or two extra could not be felt...but do not over-do-it! Also, radial tires have sidewalls that flex much more than bias-plys, so keep them properly inflated.