Air pressure for 550x19R tires?
 

I'm in the process of installing the Excelsior Stahl 550x19 radials on my '29 Town Sedan.

What air pressure do you folks who have gone down this road before me recommend?

Thanks!

Steve

Re: Air pressure for 550x19R tires?
 

Steve,

I can't really recommend any particular PSI, other then what the tire maker suggests. However, how about placing a nice pic or two of your "A" with the new tires on the ...'Barn. I'd like to see how she "stands" now.:)

Bob-A:D

Re: Air pressure for 550x19R tires?
 

Give or take: 40psi

Re: Air pressure for 550x19R tires?
 

Steve:
I have been running Stahl 550 x 19 at 35 psi for several months and am getting a very nice ride in my 31 Slant Windshild Fordor.

Marshall in Hot Houston!

Re: Air pressure for 550x19R tires?
 

Will do, Bob. I'm getting ready for a fishing trip now, so it will be a couple of weeks before I get back to that project.

A few years ago I almost converted to the 1935 16" wheels. I had gone so far as to buy the wheels and have them powder coated. Luckily, before I invested in the tires, I borrowed an extra set of mounted ones a friend had to try out. Didn't like how they looked at all! So, I dodged a bullet. People in our club who have them are very pleased. To my eye they look OK on coupes, roadsters, and pickups, but not sedans. I'm counting on the difference between the 19" and my current 21" wheels being tolerable. At least they'll still be "Model A." The tougher decision was 500 vs. 550. Finally decided to go whole hog with the 550s: They should be closer to my current outside diameters, and all of the reports I've read from satisfied users including Model A Times are for the 550s, in spite of them being not as good a theoretical fit for the wheels.

STEVE

Re: Air pressure for 550x19R tires?
 

Steve,

I'll look forward to when you post the pics. I've got a set of 18" (from '32)
wheels that I might eventually put on my '31 roadster. The 15" wheels don't look good on a Model-A to me either. ;)

Bob-A:D

Re: Air pressure for 550x19R tires?
 

Marshall in Houston

Could you post some pictures of your car so we can see what it looks like.

Thanks

Re: Air pressure for 550x19R tires?
 

Tyre pressure can be quite a thing in the sticks here.
Some people swear by the 4psi the rule.

Now, I don't know whether it applies to bias plies. It may have come about in the time of radials. Anyway, this is what Coopers say:

"As a general rule, the following can be used - for road use only: For passenger tyres, inflate your cold tyres to the recommended tyre pressure on your vehicle’s tyre placard*. Then to determine if you have the correct pressure for a given load, note the cold pressure reading. Drive for at least 20-30 minutes to ensure they have reached operating temperature and then check again. Ideally, they should be about 4psi above the cold pressure. If the pressure is more than 4psi above the cold pressure, you should add more air. That is because there is too much friction, which builds up more heat than desirable. Conversely, if they are less than 4psi above cold pressure, the cold pressure is too high. Adjust your pressures accordingly."

https://www.coopertires.com.au/media...-pressures.pdf

Re: Air pressure for 550x19R tires?
 

I agree, 16's don't look right at all. I have kept my 21's and plan to not change. Look on the tires, there will be a maximum inflation there. I keep mine just a pound or two under the max. Rides better, wear better. Different brand tires have a different max pressure rating.

Re: Air pressure for 550x19R tires?
 

Another advantage of running the Excelsior Stahl sport radial tire is that they are rated to 44PSI. If I am driving a long day at 50 mph on paved roads I'll inflate the tires to +40PSI. WOW, you can really get the old girl going with these tires! Unfortunately, I can always find a dirt road to explore whereby I'll have to reduce the tire pressure to 34 PSI or so to prevent the car from bouncing all over the place.