The dreaded drag radial wobble
 

Looking for pointers on how to fix my issue. 68 dart with stock front suspension and four link rear. BB motor with 821hp and a 727. The tires are Goodyear 31.5 x 31 x 15 with 18psi. Car makes it to the 1/8th mile then the steering wheel starts moving left and right and the car wobbles really bad. Ran bias tires for years and no issues. Switched to radials and adjusted the shocks and this happened. Any thoughts on how to fix this. Thanks for the advice.

Re: The dreaded drag radial wobble
 

How much caster do you have? Ray

Re: The dreaded drag radial wobble
 

No Fun!

Having been there and done that with different cars over the years I can tell you that many answers are found in the front end not the rear.

The lower psi of the bias ply masks underlying issues already in play. I have seen the following cause radial wobble....
* Bad front shock
* Bad rear shock
* Loose Idler arm
* Cracked steering box mount

Hope you find it easily

Re: The dreaded drag radial wobble
 

do you have radials front and back? Mixing them made my car drive terrible on the top end.

Re: The dreaded drag radial wobble
 

Anti roll bar might help with the 4 link. Try running the same pressure in the radial as the bias for a staring point. I run mine a 12 psi and have minimal problems with the wobble. Make sure everything is tight in the suspension and no slop or loose bolts. Radials need to dead hook. No wheel speed as some call it.

Re: The dreaded drag radial wobble
 

I do have bias front tires. There on a four inch wide wheel and an anti roll bar in the rear. Front end was setup for racing but that was a long time ago and I don’t remember the specifics.

Re: The dreaded drag radial wobble
 

Like said above - anti roll bar does wonders. A must have with big radial tires.

Re: The dreaded drag radial wobble
 

I do have an anti roll bar. It’s not helping.

Re: The dreaded drag radial wobble
 

I had a similar problem on my old third gen Camaro...... put a steering stabilizer on it and never happened again. I had to make some mounts, but wasn't to much trouble. I don't remember what the original application was for the steering stabilizer, but it looked like a standard shock.

Re: The dreaded drag radial wobble
 

Don't know if a steering damper is the fix, but the commonly used one is from and old VW bug , and make your own mounts for it