tire pressure

[jrock]

brand Xs say use tire pressure recommended by manufacture.I've got radials on a 53 commander. New, Studebaker recommended 26 psi front 22psi rear. What psi should I use with the radials?
Thanks
Jim

[raoul5788]

brand Xs say use tire pressure recommended by manufacture.I've got radials on a 53 commander. New, Studebaker recommended 26 psi front 22psi rear. What psi should I use with the radials?
Thanks
Jim

Go with the manufacturer. The numbers Studebaker recommended were for bias ply tires, not radials.

[j.byrd]

jrock, there will be lots of opinions on this one, I bet, but on the Sky Hawk, the 63 Avanti, and the 48 street rod truck, we ran 32 front and 28 to 30 rear and all 3 rode and handled great. The Hawk had stock wheels, the Avanti 8" mags part time, stock wheels part time, and the 48 had 6" front, 10" rear. We obviously had more narrow tires on the stock wheels, but just ran these numbers and all were fine. Radials were a TREMENDOUS improvement on the cars, and all we ever had on the truck. I also put a set on a 50 model truck, ran the same pressures, but didn't keep it long enough to make a decision other than it improved it about 99% in feel and ride.!! John

[50Ragtop]

Easiest answer is generally a tire with more air pressure will wear longer and a tire with lower pressure will ride smoother. Also, too low pressure in your tires can heat up and cause problems. Here's what I'd do. Start with 30 psi in all four tires and see how it drives. If it feels too hard, get out and drop a few pounds until you like it. Don't drive too far or too fast when you do this since they'll heat up and raise the pressure and your reading will be off. Sounds like a cruise day to me!

[whacker]

I have had some medical problems recently, and am currently pretty weak. I got my 51 Commander out last week, and I could hardly turn a corner. This week I pumped the fronts up to 40 PSI (new radials) and now I can at least steer. The slightest little bump, though, and it about jars my teeth loose. A small price to pay to be able to drive my Studie!

[Johnnywiffer]

30/30 in my LC. Rides solidly but steers like a car without power steering, which it is. Gonna try 35 next time I take it out.


John

[Warren Webb]

This is going to take some time to find out what the correct tire pressure really is. Remember most of us have not only replaced the original 4 1/2 inch wheels with 6" but radial instead of bias ply tires. Too much pressure will have the same results no matter what type of tire you use-wear will be on the center of the tread. Likewise, too little pressure will wear the outside of the tread, and lead to high heat resulting to tire failure. The examples of this are all over the freeways with portions of tire tread separation debris. Generally tires today come with 10/32nds tread depth. Buy a tread depth guage (they are cheap!) and when you have found a pressure that you are comfortable with, measure the tread depth regularly, so as to make sure you are getting even wear. I would measure all the tire grooves across the tread, but most sources say to measure at 3 locations on each tire (inner, center & outer) being careful not to measure on one of the "wear indicator bars" moulded in the tread. Tire design and construction have changed tremendously since our cars were made, so the recommendations made 50+ years ago are basically void, especially if you have gone away from the wheel size. This is a great thread for us to contriblute to but only if we state what size tires & wheels we have to the pressure used.

[Alan]

Also offset or backspace will affect how well it steers. Studes love wheels off front wheel drive cars but hate deep dish type wheels. Scrub radius.

[Gunslinger]

Modern tires run at higher pressures than older designs...35 psi, 44 psi and maybe other ratings. Old bias ply tires had a 32 psi maximum cold rating. I tend to keep my tires near the max rating for better fuel mileage and improved tire wear...under-inflated tires run hotter (and wear the edges too fast)...it's heat that wears out a tire more than mileage, assuming correct alignment and balance.

Everyone has to find what they like best for their likes and dislikes for a car. I've found that running the front tires with four psi more than the rear improves the handling in my Avanti, due to the forward weight bias.

[Laemmle]

I have 205-75-15 shoes on my 64 Avanti........I keep 35psi in all four tires with no problems.

[SILENTBOB]

Never exceed the manufacture recommended tire pressure moulded on the sidewall. 40 PSI is the fastest way to the hospital when the tire blows due to over pressure.

[GTtim]

I think the longer wheelbase cars benefit from having the pressure differential that Studebaker originally specified. Try 2 to 4 lbs. less in the rears, I'll think you'll find it will go into the corners smoother.