Hot Rods Steering stabilizer vs pan hard bar...

I believe "track bar" was '30s/'40s Ford factory terminology for a rear Panhard bar?

 

^^^ That is probably the wisest approach......^^^

 

Alldone is a kindergarten dropout. Then he graduated to asshole. Now I think he’s progressed to senile.

 

He does seem a bit "2 forceful".
I have both a Panhard and a stabilizer on the front of my roadster. It works well and I see no reason to tear off the "bandaids" to please the internet. Plus they are all polished and plated and I live by a simple rule "don't remove the shiny bits". I really like that "tuning fork" @DDDenny added a page or so back!

 

Well I may as well ask a couple of questions since answers are flowing freely.

1. I have a dropped axle, hairpins, a transverse spring, and Vega cross steering in my Model A. The car has been on the road for more than 15 years without a Panhard bar, a dead perch, the tuning fork thingy, or a steering stabilizer and I've never had any front end shake, shimmy, wobble, etc. Why would that be? Everything I've read suggests that a Panhard bar is necessary when running cross steering.

2. Our Bonneville race truck (61 Ford) has a dropped axle, hairpins, coil overs, and the tuning fork thingy in the front. We've developed a death wobble that we can't seem to figure out. We've checked everything for wear and tightness and rebuilt the (stock) steering box, built a new drag link, replaced the heims on the hairpins, and replaced the steering universals, reset the caster to 7 degrees, reset the toe-in to 1/8, 3/16 and 1/4. None of that worked so we put a steering stabilizer on it and it no longer goes into a death wobble, but it feels like it's getting ready to the whole time I drive it. Last test run with the stabilizer was 90 mph whereas without the stabilizer it would go into a wobble at any speed. What have we overlooked?

 

I would say that because the spring is under tension that is what is keeping it centered when you apply steering pressure. You haven't experienced a condition where the input from the steering exceeds the tension of the spring keeping the axle centered. Other people haven't been so lucky, some have even crashed as a result, and destroyed the car. Good engineering practice is to use a Panhard bar or some other means to keep the axle centered and not rely solely on the spring tension.

 

I'd check that tuning fork and wager that there is a bit of gap in it and replace it with a good stiff Panhard.

-rick

 

Need pic of the DRAG Link

 

1. Your A's front axle is laterally located by the spring shackles. Wobble isn't a lateral-location issue. You do have bump steer, but depending on the amount of suspension travel you have you might be too used to it to notice.

If you want to go to a more serious dynamic level and increase travel (they go together, if Colin Chapman is to be believed) you'll run up against the limitations of the spring shackle location.

2. Top-speed-oriented builds want more caster angle than that. About 12° feels right? Possibly more?

 

Wow . . . Wow . . . Wow . . .
This is F%#@ing awesome.

 

Thanks, I've suspected this was the case for a while with my Model A. I have occasionally noticed a bit of bump steer, so I'll need to address that one day.

On the truck, caster is currently at 10 degrees – the problem persists.

There is enough of a gap to allow it to work – maybe a 32nd on each side of the bolt/pin.

No pics right now – the truck is at the owner's shop.

 

Steering stabilizers are usually used in heavy unstrung weight apps IE solid axle 4X4s

 

So that would eliminate the tuning fork we have to locate the axle. What else can we check beyond caster, toe-in, and loose or worn steering and suspension parts?

 

flip the tires...or try a different set...you probley got tire walk going on..

 

disclaimer.... the person posting does not know anything about anything...

A MAJORITY OF ISSUSES ARE TIRE RELATED... I fix this problem by putting the rear tires on the front.. most complaints i get are with jeeps... tire manufactures say that tire walk will go away within 2000 miles... but some times it shows up after 20,000 or more miles... tire inflation can also cause this problem... but like said... swap the tires and see...

 

Do you have any "mechanical bump steer" between the 4 link and the drag link?

Also check Scrub Radius !!!! too much scrub radius can trigger death wobble
You do not want too much positive caster if the vehicle is lightweight [the vehicle will easily lift instead of self align]

Scrub radius can be altered [both deliberate and accidental] by wheel or hub offsets, and total diameter

You went to all that trouble adding a vertical slider [with a brace] why not simply use a Watts Linkage .
Or a diagonal Panhard bar [using a clevis on the lower Heim joints]

It has been entertaining

 

Good idea, gonna drive around for a couple years with 7.50x16s up front and 5.50x16s out back; will report back.

 

Don't know if it will cure any "tire walk" problems, but your fuel consumption will probably go up seeing as you will be constantly going uphill. Be careful you don't get a sore neck........