Air Pressure Kelly Tire

[Allan P.]

I have been trying to figure out the correct air pressure for the Kelly tires on my 64 coupe. They are P205/75/R15 97S. 3ply. Looks like it's 44psi for max load. Just seems a little high to me. Is there a safe all around cursing speed psi I can use. Any help is appreciated as I am learning on the run, a rookie.

Thanks in advance

[Jack H.]

Re: Air Pressure Kelly Tire

Max pressure rating is mfgr supplied info. You'll find newer tires are VERY different from factory original bias ply tires in their construction and have considerably different inflation pressure characteristics...

[Duke W.]

Re: Air Pressure Kelly Tire

... and the maximum load of that tire is placarded on the sidewall as something on the order of 1600 pounds, so the four tires will support double the weight of the Corvette. Thus you don't need to use the maximum cold pressure.

Somewhere in the range of 24-32 psi should be okay. The lower end will offer a smooth ride. The upper end will crispen up the steering response and handling and yield better fuel economy due to less rolling resistance, but at a slight expense to ride harshenss.

My suggestion is to start with 32/32 if a SB and 34/32 if a BB. If the ride is acceptable to you, stick with these cold pressures.

Always check and adjust pressures when the tires are cold and not in direct sunlight. Driving (and direct sunlight) heats up the tires and raises pressure by several psi. On racetracks tires pressure can increase up to 12 psi.

Modern passenger car radial tires have maximum placarded cold inflation pressures of 35-51 psi depending on the design. Higher speed rated tires usually have higher maximum placarded cold pressures. Repro bias ply tires might be placarded at only 32.

Duke

[Stuart F.]

Re: Air Pressure Kelly Tire

If you run too high on pressure and the ride is very harsh, you'll probably curse faster than you ever did before.

Stu Fox

[Bill I.]

Re: Air Pressure Kelly Tire

Allan, I run 34 all around of my 205's happy. Bill

[Allan P.]

Re: Air Pressure Kelly Tire

Thanks for the information. It was helpful and will be used.

Thanks again,
Allan

[Brian M.]

Re: Air Pressure Kelly Tire

I run 30#s all around on my small block.