Death Wobble - speedway tie rod may be suspect

Not to beat a dead horse, But I needed a shorter tie rod after changing my steering arms, I had a speedway one on before and after reading this thread I figured I would order a welder series rod rather than shorten and rethread the speedway rod.

Despite the welder series rod being 1.5" shorter it weighed about a pound and a half more than the speedway rod, and the i.d. was substantialy smaller. The speedway one looked to be DOM tubing as was the welder series rod.

Now the question is will this be enough of an advantage to offset the extra 1.5 lbs of un sprung weight? But I guess when you run straight axles you have to have the additude of "whats unsprung weight?"

At any rate the folks at Welder Series are top notch and provided great service and a quality product. They sent a couple of free catalogs that look to have some cool stuff in them.

 

On a set of Tru=Classics wire wheels I had the long style lug nuts bottom out on the stud before they were fully seated. I'd be driving along and all of a sudden this harmonic vibration would start up and get real crazy, I could stop and start up again and it would be gone. Didn't find it until the day I sold the car and was checking the brakes before delivery.

 

You were told wrong.


You don't make anything stronger
by putting a big hole in the middle of it.

Calculate the Section Modulus of the solid and tube.
Pretty straight forward stuff.

 

Consider 1.5 pounds to be cheap insurance.

 

With the same OD, which is "stronger" ?
A solid Aluminum bar, or an empty beer can ?

The beer can looks like a thin wall tube, to me at least. Right ?

A solid bar, of the same material and OD,
is obviously stronger in bending, compression, tension, and torsion.

For a given weight/ft, tube is stronger than solid
in bending, compression, and torsion.

 

Hi folks!
I'm new to the group, and must admit I haven't read all the posts here, but may have some usable input.

I have a (let's just say it's a ) model A street rod, basically a T bucket body on A rails, and can see everything when the wobble happens. I have driven this car for 30 years, 25 with the front end that Henry made.Traditional setup, Mustang steering box under the frame at the firewall. As the original front end got older, (or more subject to my punishment) The wobble started to occur, so I replaced it with a speedway total front end. Hiem joints and forged steering arms.
Guess what? Same wobble!
While driving down the road, purposely hitting potholes, and keeping my cool, I can CLEARLY see that the shimmy goes all the way back to the steering box, but the steering wheel ain't shakin'. So, in my case I believe the culprit is somewhere in the steering box.
The only part I didn't replace!
I need to get out there and go over some of the things talked about here.

I (or somebody) need(s) to get video of it happening from different angles,now that would be way cool, and help get to the bottom of this!

 

Yeah, there is something wrong here. I ran a Speedway tie rod and drag link on my 23, I have their tie rod on my 27, and both of my Sons are running their tie rods and drag links...........zero problems, zero flex.

I think you have other issues going on.

Don

 

Don, Wow this is an ol one. Did you not see the video? Light pressure on the front of the tires easily bowed the tie rod in either direction. I stiffened the the rod by adding a piece of angle to it. Gave the cross section a stiffer moment of inertia. It helped in my case. I run 10.6s in the quarter at 130. No problems. Thanks for your opinion though.

 

I never think to look at the original start date of a thread !

Don

 

yes, this is an old thread....but it's a slow morning for me , so why not post on it

as i said in my first post on this thread i make my tie rods and drag links out of 7/8" OD DOM tubing with a .188 wall. it may be overkill , but i have a BIG pile of it. with everything on the front end tight i have never had death wobble on any of my cars , or any that i have built. maybe the extra thickness helps? the only time i have ever had a wobble was in about 1970 with my stock `30 sedan that had everything worn out up front

 

Here's a thought--,

I just talked to a buddy of mine who is a lifelong motorcycle guy and mechanical philosopher.

He said: Have you ever thought it may be the same as the motorcycle death wobble due to caster angle? You know , I never thought of that!
If there is not enough caster angle the wheels won't naturally go straight!
He said- put a stabilizer on it!
I said - but that would be like giving up!
I did notice that When the car is "heavy" 3 or 4 passengers and the gas tanks are full, it has never wobbled! Probably due to the positive caster gained by the weight on the rear.

Think about it what's the setup like on a rail dragster?

I know it's still got to turn, but what about a degree or two of caster?

 

^ The only head shake I ever got on a stock motorcycle was from not having the triple clamps / steering head bearings adjusted correctly. Gary

 

I know this an old thread but the death wobble has me concerned now. It happened to me shortly after I got my 37 Ford pick up and it happened twice today. Stock frame, reverse eye spring, disk brakes. I put new shocks on the first time it happened. I have new tires on the front. The wife said she doesn't feel safe in the pickup. I think it happens when one front tire hits a hole. I think all 3 times I was going about 40 or 45 mph. What would be some of the simple things that I can check.

 

I read this....... thread, because I had nothing better to do. While there is SOME good information, most of it is misinformation and ranting. If I were you, I'd find another thread on the subject or start a new one. There are dozens of GOOD threads on "death wobble".