B-Body Buick Steering Camber

[cluxford]

61 Buick Lesabre

bagged

18's on front 20's on rear

These full size cars are designed that the wheels "camber" on cornering, that is the wheel tilts into the corner

Problem is I'm chewing through front tyres at a rate of one set per year as I daily drive this thing almost 12,000 miles per annum

I have castor and camber set to factor specs, lower control arm is parallel to the ground so no pressure on the ball joint.

I'm wondering if upgrading to aftermarket steering and suspension components may help reduce the cornering camber. Ride tech, Speedtech etc

Problem is Buick B Bodies are not the same as Chevy. Steering is at the front, not the rear of the cross member.

I don't know enough about steering geometry to know if changing to aftermarket would improve this, or not.

Would love to hear thoughts

[dale68z]

Is it wearing the inside of the tire?
What is your toe set at?

So, I take it that when you hit a bump, the camber goes negative? To prove or disprove that theory.... Use a carpenter level, or a caster camber gauge on the tire. Note where the bubble is. The jack up the opposite rear of the car, compressing the front suspension. Then recheck your camber (may be able to eyeball it if the change is dramatic enough)

this way you can be sure your theory on camber wear is accurate.

[dontlifttoshift]

all of that ^^^^

Camber doesn't wear tires, I mean it does, but it's minimal IF toe is set correctly and you don't have ridiculous amount of toe in/out through suspension travel. If you are wearing the outside edge you are toeing in, if you are wearing the inside edge you are toeing out with travel.

Are you cupping tires? That is usually cause by bad shocks or underinflation.....or crappy tires.

[cluxford]

Thanks fellas, I don't have the exact toe settings, but I did give the alignment shop (over 2 years ago now, but this has been a problem since then) the factory toe specs and they assured me they set them that way. It's been in the back of my mind to do my own check anyway, so now that will be priority #1.

To answer some of the questions:

1. It's wearing both the inside AND the outside of the tyre. Yep both. Reason is if I turn left the left hand tire tilts negative camber wearing the outside of the tire, the right hand tyre tilts positive camber wearing the inside. When I turn right the opposite happens wearing the opposite side of the tyre on each side.

I'm yet to do some testing, but all I can put it down to is geometry. essentially when the steering is turned it causes the tyre to lean "into" the corner. I'm a bit stumped as to how this can happen given the UCA and LCA are fixed lengths and can't move inwards out outwards to cause the spindle to shift it's vertical plane

2. Cupping. Nope it's not cupping. wear is quite smooth

3. Under inflation and crappy tyres. They are Continentals which I thought were decent, but I'm surprised by the wear, having said that I have the same continentals on the rear and they are in awesome shape after 2 years, barely any wear at all, so I do think the camber is the issue. Under inflation becomes more a problem towards the end of their life, as they get close to the canvas on the edges of the tyre I find I'm having to add air a lot more regularly, so it becomes a vicious cycle then

[dontlifttoshift]

1. It's wearing both the inside AND the outside of the tyre. Yep both. Reason is if I turn left the left hand tire tilts negative camber wearing the outside of the tire, the right hand tyre tilts positive camber wearing the inside. When I turn right the opposite happens wearing the opposite side of the tyre on each side.


This is with the car sitting still, just turning the wheels? It is not abnormal for camber to change by turning the wheels left and right. The more caster you run, the more camber you will gain (negative, on the outside assuming positive caster) for a given steering angle

I do want you to clarify your statement above. Negative camber is when the tire is closer to the engine at the top. Negative camber would wear the inside edge. Positive camber is when the tire is closer to the engine on the bottom, that would wear the outside edge.

Can you dig up the alignment sheet, curious what caster is set at.....actually curious about all the settings. Also, what size wheel and tire up front?

You say its bagged. Are the left and right on separate lines? Do you still have the anti roll bar in the front? You didn't respond to my mention of shocks, you are running shocks right?

[cluxford]

Donny, thanks for taking the time to jump in much appreciated. Yes I have been lax on info and apologise I do get + / - camber around the wrong way, but you get my drift.

Specifically.

Yes when standing still in the garage she tilts when I turn lock to lock.

Tyres are 235x45x18 on front

It is running a C5 vette spindle

front airbags are on separate air lines and it's running Shockwaves (integrated airbag and shock from Ridetech)

Anti-roll bar, not sure it has one from factory. Buick have steering at front of cross member other than torsion rods I don't see any other bars under there that would be an anti-roll bar

I understand more castor would create more turning camber, but what's intriguing is that there are no castor or camber adjustment shims on either side. I do want to do a castor review though. But again can only go on what alignment shop told me and they said in factory specs, I gave them the sheet below (from the shop manual) when doing so.

http://i156.photobucket.com/albums/t37/cluxford/Buick/A85F2476-FE35-4DAA-90AE-E8EABF918CC6_zps2ixrisuq.jpg (http://s156.photobucket.com/user/cluxford/media/Buick/A85F2476-FE35-4DAA-90AE-E8EABF918CC6_zps2ixrisuq.jpg.html)

[cluxford]

Thinking I might align it myself

0 degrees castor

0 degrees camber

and 3/16 degrees toe in

and see what that does.

[dale68z]

Thinking I might align it myself

0 degrees castor

0 degrees camber

and 3/16 degrees toe in

and see what that does.

You will want some + caster. Maybe 1.5 deg. Caster gives good steering feedback and is the reason your steering wheel returns to center by it'self after a turn. It does have negatives. heavier steering, and also works to jack weight to the opposite rear corner (which can be a good thing)

I aligned my 71 today... We run it on track.

2 3/8 - camber
4 7/8 +caster
1/16 toe in

[cluxford]

Thanks Dale, this ain't no racer, just a daily / cruiser.

I've read a bit about these are better with negative caster.

it drives great by the way, steering is not heavy at all at this stage.

I'll base line then go from there

Planning to do alignment in my garage with no professional alignment tools. I suspect it ain't difficult.