Well i could not find the tire pressure sticker on the door jam so i would like to know what i should set the tire pressure on these tires. The tires all say max 32PSI First time driving this car and a car with bias ply tires.
Try 32 psi and ride around. Take some curves and heavily crowned roads. Then drop 3-4 psi and repeat. The fronts on my '57 are skinny and tall. 30 psi makes the car a little twitchy. 33 cures it. Those wide ones might not be so sensitive. Rears are easy. Do a burnout and look at the contact area. Play with the pressure until the patch you laid is evenly distributed!
Back when, the average sedan ( say 3200 lbs ) rode best at around 28 PSI. Something to avoid is over inflation. The tread will wear away in the center of the footprint, before you know it. Once gone you can't get it back. If your ride is lighter than 3200 I would start at maybe 25 lbs, then see how the side wall looks. See how it handles. We do not want to see the bulge at the bottom that can found with a radial. If there is bottom bulge the wear will be on the edges. Good luck.
Back in the 60's and 70's when bias ply were common, I always ran 32lbs. on my fronts and 30lbs. on the rears. Just go with trial and error, for whatever gives you the best ride and handling feel.
I would first match the actual static weight per tire (or axle/2) vs the tire's load rating, then adjust the pressure with the same percentage.
I have the original tire pressure sticker on the inside of the glovebox door on my 1951 Ford coupe. I was surprised to see how low the recommended pressures were. I believe they were in the low to mid twenties. I will check it when I go to my shop today and post the actual numbers later. EDIT : Checked it out; it says (for 6.70/15 tires) 24 psi front and 21 psi rear.
Posted this before, A2Q works;; This has nothing to do with the new BS design thin/low side wall new ugly ****{{{{{{ But tires we should be using. Tire psi seems too be misunderstood a bit,,in regarde to using a tire on hotrods. #1 is you can not go by marked on tire psi,or psi of car factory,or any other pre marked down #= The only way to set PSI is to play some with,the tire is not on any type of normal use,so its up to you to be smart enough to know this;;; The psi of a tire depends on the load on the tire!!!!!!!!!!!!!!!!!!!!!! With car loaded and on flat ground,look at the side wall,and tread. If you see no flex in side wall near the ground,then your tire has too much psi for the load,,If your tire has more then about a 1/2in. of flex/bulge showing near the ground=too little PSI//////In between this ,is the ideal setiing< but you do need too play a few psi up or down for best feel n ride for street driving. That goes for both front an rear!! You need a small bulge,about 3/8in. so tire can do what it is made to do. Not to be for drag race settings though,that's another game,for racing !!!
yup, I wore out a set of bias plies on my corvette by running them at 32 psi. the center treads wore out quick. I looked up what the factory recommended and set them at 24 psi and man does it ride smooth now.
I've never tried this as I live on a gravel road and it wouldn't work, but I have read about chalking up the tread on your tires and going for a short test drive. Then check to see where the chalk is left on the tread. Adjust air pressure from there. Sounds good in theory.
those tires are really wide, they're gonna wear out in the center even if you run mid 20s psi in them. See how it handles with less air than you have now. Also front/rear weight bias is important, I learned that the hard way on my altered wheelbase Chevy II. Thinking about factory Corvair recommended pressure got me to figure out the problem.
I used to run as low as 12-15 lbs in 60 series bias tires on the rear. Heavier car would take maybe 20-22.
These cars are light compared to a full bodied sedan from the 50s or later. As noted, 23-maybe 25 PSI is all that most of them need. I ran 23# in the front of my T with 5" cycle tires and a 348 W motor
Are they straight bias-ply or are they bias-belted? When wide ovals came out in the '60s, most were constructed with tread belts on the bias carc*** to help keep the tread flat. That can change the 'window' of acceptable tire pressures somewhat. While not as sensitive to low tire pressure like radials, too low can concentrate too much flex in the carc*** sidewalls and lead to premature failure. As Dana says, look for the 'right' bulge.
Something else you can do is while airing up a bias ply tire on the vehicle, sitting on the ground, look from the front or back of the tire and see just when the edges of the tire lift from the concrete. Check that pressure then bleed the air off until the tire is sitting flat on the ground again. Check your pressure again, you should be very close to the max air pressure. Check your ride and adjust according to your preference.
In my channeled roadster I run 18lbs in front and 20 rear. It is a light car. Anything higher and it drives hard as a rock.
In the early 70's when I was working in a Firestone store and we were selling 2 ply Bias polyester Deluxe Champions we usually set them at 26. Bias tires don't last that long mileage wise anyhow so you want the right pressure to help them last longer.
I know this is an old thread but still useful as I have bias plys as well. I asked Coker directly and they recommended 32psi front, 40psi back on my Firestone Deluxe Champions that were 5.5x16 and 7.5x16. Take that info as you will.
If you want to know what pressure works for any tire on any vehicle put some masking tape across the tread on all four and go for a drive on a straight road. Drive carefully and stop and check the tape for wear and adjust pressure to achieve even tape wear across the tread. Works well on Bias and Radial types. JW
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