Tire Pressure

01aford

Senior Member
Have have a new set of 600 16 Coker radials.

The car seems to float a bit at 50 mph. Per Coker the tire pressure is 41 pounds.

What do you guys think if I lower the pressure to 36 pounds?
Less float?
 
What do you mean by "floating"? I'm contemplating radials for my '41 and I'd like to know what to expect.

Did you have it aligned after the new tires were installed. That made a big difference on one of my other cars.
 
Somehow in my youth I got the idea that a good universal tire pressure for old Fords is 30 lb. I'm not real young anymore... Karl
 
Have not had it aligned. But it drives very straight and does not pull.
This is the best way to decribe it: It feels like when you have overloaded your pickup and the front seems light.
 
See if the high pressure is too much for the tread...I'd get tire warmed up and then draw some chalk marks or even pencil across the tread and see if the whole mark scrubs off or just the center in a short run straight ahead. That pressure is interesting...I have only run bias tires on old Fords and radials on modern vehicles, but the radial specified pressures I have encountered have not been high.
And--is there a pressure range molded into the tire itself or is it made to look antique without all the DOT verbiage?
 
Diamondback Tire told me 36 psi on my 205/75/15 radials on my 51 Ford coupe. works fine. tire says 44 psi max on the sidewall.
 
I run 32 psi on my radials on the A with '35 Ford wheels and the ride and drive is great. I think 41 psi would take most of the benefit out of running the radials. Ed
 
See if the high pressure is too much for the tread...I'd get tire warmed up and then draw some chalk marks or even pencil across the tread and see if the whole mark scrubs off or just the center in a short run straight ahead. That pressure is interesting...I have only run bias tires on old Fords and radials on modern vehicles, but the radial specified pressures I have encountered have not been high.
And--is there a pressure range molded into the tire itself or is it made to look antique without all the DOT verbiage?

Nothing on the tire. The folks at Coker said 41 pounds. I'll take it down to 36 and give it a try when it stops raining. Just was interested to see if others had this happen
 
What type of vehicle are they on? Any idea of the gross weight ? What engine?? What type of suspention do you and any extras sway bar, stock? This would help in getting you answers.....
 
In the old days and bias ply tires i ran 37lbs and now i run 35lbs in the radials. Marv
 
What type of vehicle are they on? Any idea of the gross weight ? What engine?? What type of suspention do you and any extras sway bar, stock? This would help in getting you answers.....

1940 Coupe, stock 85 hp engine, stock sway bar, stock suspession, stock shocks. All above rebuilt.
 
On my stock suspension pick up I am running 215/75R15 in front and 235/75R15 in the rear. All are set at 35 PSI. No abnormal behavior at all. Ride is good for an old pickup and it goes where it pointed.
 
I'm running 600X16 and wanted to know if anyone else had the same issue.
Thanks
Where did they come up with 41#? Try 30#.
Just because the tire says it'll hold 40# or more doesn't mean that's what belongs in the tire ON YOUR VEHICLE.
The tires on my Porsche say they'll hold 50#. Owners manual says 30# rear and 26# front.
If I put in the 50#, I doubt the car would corner like it had Velcro on each corner but would resemble more so a Flintstones Mobile.
 
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Where did they come up with 41#? Try 30#.
Just because the tire says it'll hold 40# or more doesn't mean that's what belongs in the tire ON YOUR VEHICLE.
The tires on my Porsche says they'll hold 50#. Owners manual says 30# rear and 26# front.


Coker gave me the 41 pounds. I didn't make it up. It's the recommended pressure. Seemed high so I checked again. They advised that I can take it down but no lower then 36 pounds.
I was just wondering if anyone else had the same issue?
 
I have Coker 5.50 and 7.50 x 16 on a deuce roadster with steel wheels and at 40psi the car is like it's rolling on solid wagon wheels. Apart from that only about an inch of tread seemed to contact the road! I've got them down to 36 in front and 30 in rear now and the wear/road contact across the tread seems even. No floating and the ride is normal.
 
Coker gave me the 41 pounds. I didn't make it up. It's the recommended pressure. Seemed high so I checked again. They advised that I can take it down but no lower then 36 pounds.
I was just wondering if anyone else had the same issue?

I didn't figure you made it up :)
You say your car is stock... then how about filling the tires to what Ford
recommended back in 1940? That was 30#.
When I buy tires for one of my modern cars, I don't ask the guy installing and / or selling them how many pounds - I look either in the owners manual or in most cases, the decal within the left door. THAT is the manufacturers specification for that particular vehicle.
 
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