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How to Toe the Line.

Swampdog

Swampdog

Active Member
I drove my T about a 100 miles to day. I get a lot of front wheel wobble (shake) when hitting bumps. Smooth roads it is great. The problem is there aren't many in Louisiana.
I was wondering about toe in. How much is about right for these set ups. 1/8 inch ?
If I remember right, zero toe the vehicle wonders all over the road. Too much toe in and the vehicle won't self center when you make a turn. (plus tire wear).
I haven't got my toe in gauge out of the rafters in my garage yet, but my naked eyes it looks a little toed out.

Of course with my no-line glasses lot of things I know are straight look curved.

By the way I just had the tire balanced. I had old Ford trucks that would shake the watch off of your arm. Remember the steering stabilizer that J C Whitney sold.

Thanks

Swampdog
 
Straight up, yes, it can dance all over the place. I use 2 (6') straight edges off the rims face OR the spindles face and measure right in front of the front tires then measure to the ends of the straight edges....6' out.
The Magic number seems to be between 1/8 to a little more. Some cars are tighter than others and responde accordingly. Ruff roads I use a steering damper, Monroe gas filled, helps cushion the shock and hits to the front steering components.
Main thing is to have '0' lash in all your components....no slack at all.
I'm not a line-up pro, I just deal with straight-line motors. Those Pros I spoke of will be by shortly to get you straightened out....
 
If you have wobble when hitting bumps look for loose or worn steering components first. Check for worn king pin bushings too. If all is good then play with the toe in/out. On my T-buckets, zero in/out works best, your mileage may vary. I would try zero or a little toe out.
 
I run about 7-8 degrees of caster. Steering is a little heavy, but I like the strong "center pull" that it gives.

I also had to run a little toe out to cure a bounce that sometimes occurred at 50-55 MPH. I'm also running a steering damper. It may not be required, but it does help in my opinion.

Also, make sure your steering box is centered and adjusted. Should have a slight tight spot in the center of travel.
 
Toe-in is not what causes shimmy when hitting bumps. Your tie rod or drag link or both are probably twanging like guitar strings when you hit bumps. Do you have cross steer or traditional? Long drag link or steering link will bounce and cause shimmy. My car had solid tie rod and drag link at one time and it shimmied on bumps. Replaced them with larger diameter tubes and it stopped instantly. 1/8" toe-in is correct. Do NOT adjust all the play out of your box or you will have a worn-out box and a car that still shimmies. My car can NOT be induced to shimmy under any conditions, period. It will track hands-off even on rough roads. I'm only saying this because someone will jump in and say you "need" toe-out (which is ridiculous) or that a tight steering box will help (it will make things worse).

If you still have shimmy with standard tie rod tubes, go to thin wall, larger diameter tubes. I've driven my car for 7 years with 1/8 toe-in and recommended play in (Corvair) box and it has never shimmied ONCE. If you replace your tubes, the shimmy will stop. Worn kingpins or ball joints will show up as knocking, not shimmy.

Your T should not shimmy on bumps any more than your family car would.
 
roadmonster said:
Toe-in is not what causes shimmy when hitting bumps. Your tie rod or drag link or both are probably twanging like guitar strings when you hit bumps. Do you have cross steer or traditional? Long drag link or steering link will bounce and cause shimmy. My car had solid tie rod and drag link at one time and it shimmied on bumps. Replaced them with larger diameter tubes and it stopped instantly. 1/8" toe-in is correct. Do NOT adjust all the play out of your box or you will have a worn-out box and a car that still shimmies. My car can NOT be induced to shimmy under any conditions, period. It will track hands-off even on rough roads. I'm only saying this because someone will jump in and say you "need" toe-out (which is ridiculous) or that a tight steering box will help (it will make things worse).

If you still have shimmy with standard tie rod tubes, go to thin wall, larger diameter tubes. I've driven my car for 7 years with 1/8 toe-in and recommended play in (Corvair) box and it has never shimmied ONCE. If you replace your tubes, the shimmy will stop. Worn kingpins or ball joints will show up as knocking, not shimmy.

Your T should not shimmy on bumps any more than your family car would.
Click to expand...

I have a cross steer . Speedway 23t deluxe I think.
 
I have tried mine from 3* to 11* and it has not made any real difference. I'm currently around 7* IIRC and it makes for a heavier steering wheel. I can't remember what my Toe is set at.
 
It's possible your box is too tight. You don't want the Pittman arm fighting the drag link when it does bounce. Speedway has weld bungs for larger tubing for strong links that don't bounce. But try adjusting your box first. When driving straight ahead, you should have 2-3 inches of free play from center. A tight spot in the center means your box is too tight. This is from the Corvair manual, but true for Vega boxes too.

I think your cross link is bouncing and fighting your Pittman arm due to a too-tight steering box. The tie rod bounces at a lower frequency and both feed back into the steering arms. The result is shimmy.
 
roadmonster said:
It's possible your box is too tight. You don't want the Pittman arm fighting the drag link when it does bounce. Speedway has weld bungs for larger tubing for strong links that don't bounce. But try adjusting your box first. When driving straight ahead, you should have 2-3 inches of free play from center. A tight spot in the center means your box is too tight. This is from the Corvair manual, but true for Vega boxes too.

I think your cross link is bouncing and fighting your Pittman arm due to a too-tight steering box. The tie rod bounces at a lower frequency and both feed back into the steering arms. The result is shimmy.
Click to expand...

My tie rods are 7/8 inch, just measured. I did tighten up my steering box right after I got the car. I guess I'll back it out some.

Thanks

Swampdog
 
I replaced my steering rods with larger ones from RPM. The TP ones were tiny. Ron at RPM cut them to length and threaded the ends (LH and RH). I added some 5/8" rod ends to that. I really didn't notice anything different than the smaller tubes but I felt better about it. One thing I have found is Louisiana roads suck (I'm sure you know this) but my car jumps all over the road here. When I go to Biloxi, Tn or Ohio the car drives a lot better.
 
Swampdog said:
My tie rods are 7/8 inch, just measured. I did tighten up my steering box right after I got the car. I guess I'll back it out some.

Thanks

Swampdog
Click to expand...
I took about 3/4 turn out of the steering box. I now have about 2-2 1/2 inches freeplay at the wheel. Test drive was 100% better. I had no side to side wobble on the same roads that were setting it off.Went from Henderson to Breaux Bridge on I-10. Cruised at 63-65 MPH (GPS) , speedo shows 80. I guess I need a couple of teeth on my speedometer gear.
 
Sounds great. The free play creates a small dead zone which allows the car to track by itself (with proper caster and toe-in) and still have responsive steering. You don't have to steer it to keep a straight line. It's just enough slack that the tie rod and cross link can resonate at their natural frequencies without hammering your suspension.
 
I know we're all supposed to be "politically correct" & warm & fuzzy , but the suggestion that somehow driving a vehicle w/ purposely "loose" steering is good just blows me away ! If your front wheels shake or wobble , something is wrong , period . Running the steering gear loose to mask that is just dumb !!
dave
 
2old2fast said:
I know we're all supposed to be "politically correct" & warm & fuzzy , but the suggestion that somehow driving a vehicle w/ purposely "loose" steering is good just blows me away ! If your front wheels shake or wobble , something is wrong , period . Running the steering gear loose to mask that is just dumb !!
dave
Click to expand...
You read it on the net, it has to be true!
 
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