1949 Special Deluxe Radial Tires

[Tim Larson]

I will be getting new tires on my 49 Plymouth the end of the week and am still undecided on the exact size to go with. 

 

Unfortunately I won't be going with wide whitewalls this time. Too much money. 

 

That being said, I am curious what experience everyone else has had with installing modern tires.

 

I appreciate the input!

 

 

[Cold Blue]

I got rid of the wide white walls which were bias ply. They handled terribly, followed every groove in the pavement, and made driving not so fun. I went with Toyo Extensa tires, P215/75/R15's. What a difference! Ole Bessie drives down the road straight and true, does not follow grooves, and steers easier than those wrenched old bias plies. I have the white sidewalls that are the narrow ones ( thats all that is available in this tire line) and I like the looks of the narrow ones better! They were installed by a small shop not far from me that had an old dude (like me..) that knew about the left and right hand thread lugs bolts and how to balance them so the wheel weights were all inside, and not showing. Really pleased with the Toyo's!

[Silverdome]

I'm running Hancook P215/75/R15's on my '48 and they seem fine and dandy.

[Loren]

Just my two cents.

If you go with Radial tires, you might want to consult with a real good alignment shop (or several). Radials respond better to more caster than Bias Ply tires.

Seventy years ago engineers only had Bias Ply tires to work with and their focus was on extending wear, which was in the 15 to 20,000 mile range if that. WiKipedia, that great oracle of knowledge says radials like 7 degrees of caster where Bias Plies like considerably less. We live in the 21st Century and our cars are forced to deal with what is available at a reasonable cost, might as well help them adjust to modern reality. From the Plymouth Manual Caster is -1 to +1 with Zero preferred, which is a long ways from 7 degrees. My knowledge is pretty dated (I last worked in auto repair in 1986) so I am a little fuzzy on Caster vs King Pin Angle (which is 4 3/4 to 6 degrees). Seems to me they basically do the same thing, just in a different place (one adjustable and one usually built in). So adding 1 degree of Caster might satisfy the tires and still remain within the specs. 

[dhrandy]

My '50 Plymouth Special Deluxe currently has radials, but are in need for an upgrade.  They are pretty old, couldn't even find them with Google.  My current size is 215/75R15 and I'll stick with that size.  I'm currently looking at a brand called Vitour Galaxy R1.  The main reason I'm purchasing them is like you, they have a wider white-wall, 1 3/8" and are cheaper than the Coker's at $99 each.

[Dan Hiebert]

Caster does not have to be increased when changing from bias ply to radials, but it helps to do so.  7 degrees positive is too aggressive for these cars if you're not going racing, you only need 2 degrees positive when switching to radials for a nice driving experience.    

[Tim Larson]

The current tires are wide whitewalls 6.70-15 from Sears! So you know they are quite old. The spare has never been used as it still has the blue protection on it. 

[soth122003]

My 48 Plm SD is running Hancook 205/75/15. The provide a very smooth ride.

 

Joe Lee

[Loren]

I think Dan Hiebert has the right idea.

I might try the factory setting First as a baseline, then a degree more positive and if all is well then the second degree.

If you're lucky to find an old timer, he's very likely already done a 1949-54 Plymouth several times and knows exactly what works.

If I still lived in Southern California, I know exactly which alignment shop I'd go to.

[Tim Larson]

I went with 215/75/15 Toyo tires. They ride very nicely and the speedometer is very close to accurate.

[1949 Wraith]

215/75-15 here as well, on my '38 with later 15 inch rims great ride. Moving to radials makes driving so much more pleasurable. I have the Coker Nostalgia Classic on a close to period correct '41 Chrysler but they do not ride as well as the wider modern style radials.

[lepic56]

what tire pressure are you running with radial tires??  same as the shop manual 25PSI???