Steering Issues

[KevinLiner]

I just recently fired up my 73 cuda after a 5 year restoration. First drive, it pulled pretty strongly to the left side, requiring continuous correction to the wheel (holding off-center to the right. Since this was a body-off “rotisserie” restoration, it would seem to be a reasonable assumption to have an alignment done as the k-member, rear-end, etc. was removed and re-installed. After the alignment, it still pulled a fair amount to the left. The following are checks/adjustments thus far, after alignment.

Still pulls slightly to left and wheel is still off-center to the right while driving.

All the suspension components are new and right. Nothing appears to be bent or out of location.
Adjusted front ride height before alignment ; to within 1/8” side to side before alignment. Ride height remains level.
All tires are new P245/45R17 BFG Comp T/A. , balanced and all have same 32psi pressure.
Switched front left and right tires/wheels around .
Adjusted new power steering box for minimal play in steering wheel.
Raised car. Started engine and Adjusted valve body to center wheel and stay centered. (It was indeed assisting to left before adjustment.)
Steering column shaft reference mark measured correctly at 13/16” from coupler per factory manual.
Measured rear axle and spring perch to reference point on frame each side. It is “dead nuts” square.
The passenger (right) side front tire “appears” to set ahead of the left side as it measures closer to the front of the wheel-well than the left side. This would indicate a possible caster difference from side to side, but would seem to make it pull to the right?
Though better that before these adjustments, it continues to pull slightly to the left and steering wheel off-center (to the right) for correction.

What am I missing?

Thanks,
Kevin

 

[heminut]

First thing I would do is dial in a LOT more caster. I'm running 3 degrees positive caster and the car handles great. These Mopars can take a lot of caster.

 

[KevinLiner]

Oh BTW
The wheel bearings and brakes all good. No pull from brakes. Tires spin freely with no runout.

 

[Challenger RTA]

Setback.

 

[heminut]

Setback.

Well, that's very informative! What are you referring to?

 

[Challenger RTA]

Well, that's very informative! What are you referring to?

Had to find something that had an explanation. Some vehicles have it built in. in short it compensates for the crown of the road.

 

[Xcudame]

Get some Moog K7103 offset bushings for the upper control arms. Then dial in as much caster and camber as you can. You will love the handling difference!

 

[KevinLiner]

Setback.

View attachment 112287

Trying to absorb this. But, really has no explanation of how to correct or compensate. Obviously a bent frame will make a car go sideways down the road and cause it to “dog track”. My rear end is dead nuts square to the frame. Not sure how to correct “setback”. I understand about the crown on roads, but not all roads are alike. Also, empty parking lots don’t have a crown. Perhaps I should try driving down the middle of the road (with no traffic of course )to straddle the crown and see what happens. At any rate, any idea how to correct? Will an 1/8” total rear toe and/or 1/4 degree of thrust angle cause this?

 

[Challenger RTA]

Dose the steering wheel find center when you come out of a turn? or do you have to force it to correct.

 

[Challenger RTA]

I would pull thesis measurements.

 

[heminut]

Had to find something that had an explanation. Some vehicles have it built in. in short it compensates for the crown of the road.

I've never heard of "setback" in anything to do with wheel alignments, and I did wheel alignments at a dealership for 5 years. Usually, road crown is dealt with by having the left front wheel camber a little bit more positive than the right front wheel.

 

[heminut]

Dose the steering wheel find center when you come out of a turn? or do you have to force it to correct.

With the very small amount of caster he has I'll bet he has to turn the wheel back to center.

 

[Challenger RTA]

Talking about frame alignment. SAI Steering follows frame. Rear spring and hosing where off. just pointing out what to look for not what is wrong. pull a tape from front wheel to back wheels on both sides. More caster will or might fix it. but what is wrong?
Axle housings can become bent from impacts. If you see an axle with a difference in toe greater than .50 degrees, look at the axle for possible damage.

 

[Chryco Psycho]

Factory setting were for Bias ply tires
for radials you want to max the caster , 1/2* of neg Camber & 1/8" of toe in

 

[Ricks72Chlgr440]

I bought adjustable upper control arms from BAC so I could get more caster. I had the alignment tech go to +4.5. Really helped with the stability of the car. No longer does it follow every rut in the road. Next time you get an alignment, have the tech use the max street/performance settings from the skosh chart. Your car will thank you.

 

[cuda joe]

cars are squirrely with so little caster .you need more caster I did what xcudame said with off set upper control arm bushings got the caster up to 4 deg positive i world of difference they also sell upper tubular control arms they do the same thing

 

[KevinLiner]

Update to my steering issues:
So, after reviewing my alignment report making all other steering and giving some thought, I decided to focus on the thrust angle and rear toe. I made a number of frame measurements and everything was square EXCEPT…. I know that I wrote that my rear axle was “dead nuts square” which was true in that it was square within its mounting location. But, I found that the LH front spring hanger perch bracket was 1/4” closer to the front of the car than the RH side which placed the rear left wheel ahead of the right wheel causing the .29* thrust angle that caused the car to “crabwalk” or “dog track”and the steering wheel to be off center to the right.

So, now I start to look for correction by shimming the left side front spring hanger. Saw that they were (supposedly) available from Hotchkis #3003 through many vendors and after reading the ONLY example I could find of an actual installation here:
Gallery: Thrust Angle Adjustment with Mancini Racing and Hotchkis Sport Suspension - Mopar Connection Magazine | A comprehensive daily resource for Mopar enthusiast news, features and the latest Mopar tech
After reading the article, I chose to buy some from Summit Racing. A pack of (6) 1/32 shims #3003 cost me over $70 with tax and shipping. Picture #1 below is a picture of the shim (supposedly for a 70-74 E body)) from the installation instructions. Picture #2 is the actual shim that comes in the kit and according to HOTCHKIS, the only one they produce. Picture #3 shows how the shim would fit (or NOT fit) if you were to attempt to “slide” them in from the bottom AS IS NECESSARY unless you remove the spring mounts from the car! Picture #4 shows that they might actually fit if installed upside down; as in REMOVING THE SPRINGS. Bottom line…. They don’t work and will NEVER work on a 70-74 E-body with stock spring mounts and the corresponding factory spring mount hole location in the perch bracket. When I talked to the tech/sales rep at HOTCHKIS he said: “Yes, I see how they won’t work. They must be for our spring mounts.” Uh, I don’t think so unless you want to drill new holes in the perch plates. So, I don’t understand how they worked on that 69 Dart in the article above. Are 69 Dart spring hangers different than the ones an E-body? Moving on…. Picture #5 is of ones I bought from BERGMAN AUTO CRAFT here in (Hempstead) NC. I bought (4) 1/8” shims (the only size he has) for about $39. Yes, they look like the ones in picture #1 below. These actually work PERFECTLY.

It is ALARMING to me that SUMMIT and ALL of the other vendors would sell these as fitting E-body cars without actually verifying the fit!
Now… I decided to install 3/8” of shims based on some rough calculations (even though my rear ended measured 1/4” forward) AND what it took (1/8”) for those guys to correct .08 on that 69 Dart.
They were very easy to install. I just barely took the weight off the axle with a bottle jack under the rear subframe section with the wheel on the ground which relieved the preload from the springs; loosened the bolts, lightly pryed the mount back and lightly tapped in the shims. Took all of 15 minutes!
Returned to alignment shop. Picture #6 is of the original attempt at alignment. Picture # 7 is the second alignment. As you can see, the 3/8” shims moved the thrust angle from .29 to -.17. So, we pulled out one 1/8” shim for a final thrust angle of -.08 with 1/4” of shim.

THE BOTTOM LINE:
Now the car drives nice and straight, no pull, steering wheel nicely centered, and returns to center fairly good even though we could achieve only about 1 1/2* of positive caster and still have some negative camber. Front and rear toe is nearly optimal.

PLEASE Do NOT buy the #3003 shim kit if you need to correct the thrust angle on your stock E-body car. Use the ones from Peter Bergman at BAC.

I apologize for this lengthy post but just wanted to get the whole story out there.

Kevin

 

[Challenger RTA]

A couple of typos above.
LH was 1/4” closer to the front of the car than the RH.
shim, not sim.
69 Dart, not 60 Dart.
Spring mount hole location, not hike.
Toe, not tie.

If you would like to correct typos. click on Edit on the bottom left. Also you can delete. Enter a reason. typo or what ever. I think it has to be done in a few days. Thanks for the follow up.

 

[Xcudame]

Peter Bergman is a great guy! Glad you got your car handling better. Now you can enjoy driving your 73 Cuda!

 

[KevinLiner]

Thanks. Now the six pack tuning….