I recently got new wheels/tires, so had my car realigned. It is now quite scary to drive spiritedly. From the reading I've been doing on here, I think I need more positive Caster. But I'm not sure if that's the only issue?

Here goes:
'76 Dart Swinger LBP disk
Manual steering
225/50R16 Yokahoma's
1yr/12k on a complete suspension overhaul/upgrade...
1" FFI T-bars, 1 1/8" Addco sway bar, Eddy IAS shocks, ESPO 6 leaf in rear, etc.


Current alignment:
Caster L: 0.4deg R: 0.3deg
Camber L 1.0deg R: 0.4deg
Toe L: 0.15deg R: 0.15deg

Not only does feel unstable and wander all over the place, when I push it into a corner, once it 'sets' it cuts harder. As in, midway though a hard corner, it will dive harder, ruining my line (and scaring me half to death). I have read something about that possibly coming from preload on the sway bar? However, I don't recall that from before the new wheels/tires/alignment. Perhaps I was not able to push it that hard on my old 205/70R14BFGs, but I doubt that...

Any input would be greatly appreciated.

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Looks like you got stock alignment settings or close. If this shop won't do custom settings go elsewhere. The original settings were for ancient bias ply tires and really soft springs. More positive caster will help stability and make steering effort a little higher. The positive camber is hurting the front grip and you may be understeering until mid corner, but I'd have to drive the car to be sure. It could also be a bump steer issue. You can check for serious bump steer by putting the car on jack stands and moving a front wheel up and down with a jack. If you see the tire turn in or out as it goes up and down you have bump steer.

I have my '67 Valiant set to max positive caster and about 1° negative camber. Unless you drive super slow around all corners this has little impact on tire wear. In fact if you drive aggressively it can increase tire life as you won't be taking the outside edge of the tread off as quickly.

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Joshua

Sounds like a toe problem, especially if you have some big offset wheels.

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Official Cookie and Mater Tormentor.

I've used this shop before, and the tech is familiar with old Mopars, etc. I was actually quite surprised he set it stock. I will certainly look around to find somewhere else if it comes to that, though.
1" T-bars, and my rubber bump stops are trimmed from when it sat lower, so I'm doubtful. But I'll certainly check it out!
Stock Crown Vic steel wheels. 16x7 with 4.25" or 4.5" backspacing, I don't recall offhand.


On a side note, the last alignment that felt more stable, was set with power steering in place. Then I swapped out the boxes, and liked the road feel that gave. For what it's worth...
I'm headed down I5 ~the 9th of next month. I'd be more than happy to let you throw it around if you'd like.

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If you want to check the bump steer more than the torsion bar will allow, then pull the bar. My '96 Dakota had wicked bump steer after I installed Beltech spindles. You could see the tires toe out when you jacked up the truck.

If you're still having handling problems when you're down this way I'd be happy to drive the car.

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Joshua

Sometimes my car won’t take a good line throughout a full ark depending on length of radius & speed. In other words it will tend to “self dial-inâ€￾ more turn by itself pulling with vigor in the direction of the radius.

By chance I had the power steering pump belt off the pump for a few hundred miles this summer, and the car would track very dependably around bends, tight or long sweeping, and reducing radius turns such as a clover leaf interchange has.

The problem is my steering box is a sloppy mess, and over assist from a slight steering wheel movement will upset the line mid turn.

Additionally, I have found that some alignment shops don’t “firstâ€￾ set ride height correctly, if at all per FSM. Or, after they do set it, while adjusting caster, decide to change the height to get a bit more adjustment. A maladjusted height (one side higher than the other) will cause all kinds of handling problems at speed, and protesting power steering noise at close to full lock in parking lots.

I would get out your FSM, and with car parked on a level floor, check ride height.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

A tight steering box is a great thing. I don't get any self steering during a corner. Manual steering on all my cars too.

Good spirited street settings with stock bushings and low profile radials:

Caster: +1.5 to +3 deg
Camber: -0.6 to -1 deg
Toe: 0.1-0.2 deg total

You can add more caster if you have the offset bushings, but will be harder to steer at low speeds. More neg camber will give a bit more bite, but wear the tires a bit more.

Happy motoring,

Lou

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Home of Slant6-powered fun machines since 1988

(Just a note on steering gearboxes for those of us in western Wash. state- Redhead Steering in north Seattle is great for steering gearbox overhauls. They have done several of mine, never any take-backs.) Now, back to the discussion....

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"Louise", a 1976 Dart Custom project, (now sadly reverted to being just an "organ donor" to our other project Darts.)

Wjajr: This is not a steady change, but a rapid one. Think on/off. Also, I tossed the power steering for a manual box 10 months ago, and couldn't be happier about it.

Lou: Thanks for the 'revised' settings. I do indeed have the offset bushings, and don't mind the low speed struggle. (I have ~31x8 knobby tires on my truck, and just nixed the power assist in that rig too...)

Louise76: I'm one of us Western WA guys. I will certainly keep them in mind when the time comes. If you wouldn't mind, PM me what they charged?

I put the car in the carport tonight, and will check the bump steer and ride height in the morning.

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I'll second Lou's alignment specs. I've been using almost identical specs for years, and they feel great. Make sure the shop sets both sides identically, as opposed to the factory crown compensation setting.

Zorg: Bingo! On & off is a good description. Also, on & off for an opposite direction correction for the initial dart… Rather unsettling at times. Other times the change is slower if the steering wheel is stable in two hands, while an arm is pressed tightly against the door & arm rest to limit any wheel input.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

It may not be your problem, but years ago I developed an internal leak in the control valve atop my '71 Plymouth's power steering box. It would boost away from center... the fix was easy.

KBB_of_TMC:
Naw. I installed a kit for that control valve a few years ago. Problem is way too much play in the gear.

Fix is to replace the box with a Firm Feel unit this winter.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

That is classic toe problems.

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Official Cookie and Mater Tormentor.

GRRRR. Well the ride height is off 1/2" side to side... I told the shop in no uncertain terms, not to measure off the sheet metal, as the wheel arches are off, you guessed it, 1/2"!

As for how Joshua was describing bump steer. The driver side looked fine, but the passenger side definitely turned outward as soon as I started lifting it. (I didn't pull the T-bars).

I also noticed there is a slight amount of play in the steering box, which is probably compounding the issues. Time to open the FSM again, and figure out how to adjust that.

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