Radial tire alignment

[vacreeper]

My 67 was equipped with bias tires from the factory.I am replacing these 9.15x15 tires with 225/75x15 radials. As radials ride/drive much differently than bias they require different camber/caster/toe in. I have searched for some guidance as to what works but have come up empty. Does anyone have suggestions? Thanks for any help. Steve

[papawayne]

I'm not sure I ever knew that. I've certainly never bothered with it. Wayne

[frasern]

I worked for a very short time for a crappy alignment shop in 1981 (I don't miss that place). At that time everything was set the same except Ford trucks. I think they were 1 deg. pos camber and caster, 1/4 inch toe in. Toe could be reduced to 1/8 for radials, but usually wasn't. I was just the parts replacer, didn't do the alignments, so my memory may be sketchy.
I have been out of that loop for a long time, newer vehicles have much stricter specs, and need to be more carefully followed.
My '67 has 235/75 15, which are exactly 9.25 inches wide, 225s will be 8.9 Also they are about 2" shorter, which will affect the speedo.
(9.15 was the width and height of the original tires in inches, forgive me if you already knew that.)

[frasern]

I checked the manual, -1 1/2 caster, +3/4 camber, so I guess my memory is flawed. Toe in is 1/16 to 3/16, I would go as straight as possible, and turn it in slightly if you feel it's wandering.
My tires just barely contact the frame bolts on the steering box. the tread width on newer tires is as wide as the casing, where the old school ones were much narrower at that spot. That is where the contact is. A bumper on the A frame side should solve that, but it hasn't been a problem, so I haven't added one yet.

[Mike]

It shouldn't make much difference. Make sure all the steering and suspension parts are good, put new tires on it and get it aligned. If it shows signs of problems a good alignment tech should be able to correct it.