Radial vs. bias ply specs

[dgs]

Hey folks. I've got a queestion about the '67 - '69 'birds that came from the factory with radials. What are the differeces in the alignment specs and are there differnt suspension bushings, driveshaft bushings or other parts? I'm trying to decide if to buy radials or bias for my '60 and I'm getting conflicting ifo on the differences in th car. I know that these '67 - '69 'birds were offered both with radials and bias so the service manual, parts book, etc should show all the differences. That should help me decide what to do.

Thanks for your help!

[ 11-01-2002: Message edited by: dgs ]

[Joe Vandatta]

I put radials on my 66---changed nothing and it roads out fine. I would put on a set of radials.
Joe

[dgs]

I appreciate your comments, but I am confident that there may have been several differences on the cars that were factory equiped with radials. I read a very comprehensive article in the Spring 2001 issue of Invention and Technology magazine on the intruduction of radials in the US. They mentioned several problems that cars made for bias tires exhibited when using radials. My '60 shows them all, to some extent. Wandering on the highway (needs about 15 degrees of steering to keep it in the lane), harsh over expansion joints and excessive road noise from the tires. The article mentioned new alignment settings, revised suspention bushing geometry and new 'isolators' in the driveshaft. However, I haven't found anyone to verify any of those things except the alignment settings (0 - 1/16" toe in instead of 1/16" - 1/8" toe in). I know that the thunderbird in either '67 or '68 was the first American vehicle (along with the Lincolns of the same year) to offer radials. I'm hoping some Glamour Bird enthusiast out there will be able to check their shop manual or parts book to find out if there were actually diffent parts in the standard suspension vs. the 'Radil Tuned' suspension.

Why do I care, as an owner of an older 'bird? Well, my car needs tires and my gut says go with radials, they're better. Well, now I think maybe for my older 'bird, maybe I should go with bias instead. I'm not sure my car can be properly set up to run it's best with radials.

Oh, and it has kinda become an obsession to find out the lost information about what is different between the two tire types.

Thanks for humoring me. :D

[Joe Vandatta]

A good front end man (and they are hard to find) can answer your questions. Don't let them tell you they don't have the specs--a good one does.
Joe