Packard Forum Index » Post-War (1946-54)

Chilton's, MoToR Manual, an early '46 Packard spec sheet all give different caster, camber, toe in. There are no alignment figures in the brown 1946-50 Packard Shop Manual.
I'm running correct 7.00 x 15 bias-sized radials, standard 127-inch wheelbase, on the usual suburban byways and freeway, if that matters.

I’m not an expert of tires but from what I understand you can just about throw out the book when converting to radials. Some of the factory adjustments are specific for bias ply as, of course, radials did not yet exist but apparently they have different requirements than the original tires had.

I only have the shop manual for the '37 120, but I suspect it is the same style suspension.
Toe-in: 1/32" to 1/8" measured at approximately hub height
Camber is desired at 1degree, but can be a minimum of 3/4 degree and a maximum of 1 1/4 degrees is permissible
Caster is 2 1/2 degrees but a minimum of 2 and a maximum of 3 is permissible.
Hope this helps.
Bob J.

Quote:

I have read the same on several sites, particularly when it comes to caster. I don't know if there is a formula so to speak, but it would be interesting to know. Maybe a place like Diamond Back would be able to provide some advice?

BTW, I put conventional tires on my '53 Cavalier, in part because I got a great deal from a club member, and in part I just like to keep things as original as possible.

Turns out I should be ignored once again. The radial tire is a completely different animal, I guess a good alignment shop could take the bias ply data and translate that to a proper one for your radials.
Sorry.
Bob J.

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Alignment specifications are given at the end of the Front Suspension subsection in Section III of the 1946-50 Service Manual

Don't be sorry Bob J, this is a good top of conversation. Because I put bias ply tires on my car I didn't get far in my research on this topic. As Don mentioned our cars were not designed for radials, but lots of guys run them and like the ride. But I have also talked to guys that don't like how their car handles with radials, which is maybe something that could be corrected with adjusted wheel alignment specs.

I would be curious to know what others, that are running radials, have done for alignments, if anything different than factory specs.

I ran radials on my 51 200 for years with no problems. My local tire shop aligned the tires and it tracked true and handled well. The only issue was starting from a stop it required some muscle to turn until you came up to speed.

All I wanted are the alignment specs. Howard (HH56) steered me to Volume 19, #10, October 1945 Service Counselor here in Big Kev's Literature Archive, which, it turns out, is what I already have on hand, as mentioned above.

Since no one seems to know better, I'll take those specs and those in my 1940-1953 Chilton's Auto Repair Manual to the alignment shop and flip a coin. Was simply hoping someone driving a car like mine would flip the coin for me.

As I understand, caster is generally decided by stiffness of steering. Too low and the steering will not self-center properly. Too high and it will be too hard to turn the wheel to lock when driving. Likewise, toe-in helps the car track straight since by the wheel turning slightly, one tire will be made straight and the other more turned, so to drag the steering straight again. These two could probably be set satisfactorily by trial and error, in that order.

Camber depends on the tires, weight, and handling characteristics. Its purpose is to tilt the wheels in slightly so when cornering the centrifugal force acting on the outer hub will distort the tire and make the contact patch larger. Apparently automakers find this value by physically pulling the car around in a laboratory based on the expected acceleration encountered in use. I'm not sure how this could be easily replicated DIY, but it's probably not too critical except for emergency or sporty driving.