Camber confusion

[Bob Johnson]

Negative or positive that is the question. I have read conflicting specifications on the correct camber for a stock Model A. First a definition. All seem to agree that negative camber is when the tops of the wheels are closer together than the bottoms of the wheels. And Positive camber is when the tops of the wheels are further apart than the bottoms of the wheels. Most also agree that the difference should be 1 13/16". If that difference is for the wheels then at 19" the angle would be 2.7 degrees. For a 21" it would be 2.5 degrees. Most drawing show the measurements at the tops and bottoms of the tires not the wheels. The tires are around 28" tall. So the angle would be around 1.85 degrees. Is it distance between the tires or the wheels that is measured?

As for the positive or negative camber. Most general automotive information sources say that you should have negative camber. Positive camber will cause poor steering and uneven tire wear. So I thought that the Model A would have negative camber. However many sources state that the wheels (tires) should be further apart at the top than at the bottom (positive camber). Which would cause excessive tire wear on the outside edges of the tires. Some information states that the tops should be closer together than the bottoms (negative camber). Which is correct? If it is positive camber then why?

Bob

[Ron in Quincy]

Positive camber is correct; it is built into the front end by the axel and spindle; a bent axel is usually the cause of problems. If every thing is correct, setting the toe in correct take care of tire wear and easy steering.

Ron

[100IH]

Camber makes the wheel want to turn out in the direction that it is leaning. With equal camber both wheels try to pull to the out side thus compressing the tie rod and removing the slack at the steering wheel. With modern cars with today's suspensions the left wheel frequently has more camber than the right to combat the tendency to drift downhill to the right side of the road because of the crown of the pavement.

[Patrick L.]

These monster were made in the early days of folks trying to figure steering geometry. But, at the lower speeds these things were operated at due to the soft rough roads, it worked out OK.
Ford says the caster should +5º, thats a lot. He also says the camber should be +1.5º which is also a lot. He also said early on that the toe should be [ I think] 3/16" and later changed that to 1/16" as roads got better/harder.
I've bent quite a few Ford axles but not an 'A'. If I did I think I'd set camber at 1/2 maybe 3/4º.

[BILL WILLIAMSON]

I sight my camber by EYE, if them dudes look straight up & down & is the same on BOTH sides, THET DUDE IS AOK!
On CASTER, IF the axle looks proper shape & NO apparent "tweeks" & the wishbone looks like NOS, then your caster is AOK.
What's left? Adjust your front hub bearings, set your tire pressures, & adjust your TOE IN. (REMEMBER, we ain't goin' to the MOON, in this thing!)
Bill W.

[harleytoprock]

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Would there be any issues with 0* or neutral camber on a model A? Most of us drive on hard pavement and with overdrives we're doing 60 mph. Maybe closer to modern alignment specs might help handling and tire wear.

[Synchro909]

Negative camber is standard setup on radial ply tyres. I recently had a young bloke try to tell me that the king pins should be forward at the top, back at the bottom. Same thing - that's OK for radial tyres. Maybe the OP is getting some of his information from someone who only knows radials.

[BILL WILLIAMSON]

Originally Posted by Synchro909

Negative camber is standard setup on radial ply tyres. I recently had a young bloke try to tell me that the king pins should be forward at the top, back at the bottom. Same thing - that's OK for radial tyres. Maybe the OP is getting some of his information from someone who only knows radials.

Sounds like the OP is getting info from a bloke that is TRYING to sound "intelligent" & has his info GARBELED/MIXED UP That kind of person is EASY to spot, his mouth is ALWAYS OPEN & he has NO EARS
Bill W.

[KR500]

Camber is called for to put the weight of the vehicle on the inner or larger wheel bearings. Equal camber on each side is beneficial as opposed to say 1 degree on left side and 3 degrees on right. Equal measurements of caster all better if equal and caster can vary 2-3 degrees with no adverse results. No bearing of a crowned road.

[Synchro909]

Originally Posted by KR500

Camber is called for to put the weight of the vehicle on the inner or larger wheel bearings. Equal camber on each side is beneficial as opposed to say 1 degree on left side and 3 degrees on right. Equal measurements of caster all better if equal and caster can vary 2-3 degrees with no adverse results. No bearing of a crowned road.

I was always led to believe that to have the weight of the car on the larger bearing, wheels were made with a "dish" shape at the centre so that the middle of the tyre was in line with the larger bearing.

[BILL WILLIAMSON]

Originally Posted by Synchro909

I was always led to believe that to have the weight of the car on the larger bearing, wheels were made with a "dish" shape at the centre so that the middle of the tyre was in line with the larger bearing.

EXACTLY CORRECT, Synchro It's just a COMMON SENSE DESIGN!! Then some Hot Rodder installs some DEEP DISH wheels & throws the whole design OUT THE WINDOW
bBill W.

[katy]

Most drawing show the measurements at the tops and bottoms of the tires not the wheels.

You seem to have forgotten that the wheel is a combination of parts, the rim and the tire.

[Patrick L.]

There is a lot of good information available, just look at those in the business such Hunter, Bear, Bean etc.