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Correct Tire Pressure for 165R15 Tires

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peterh

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I have 165R15 tires and can't seem to find what the correct pressure should be. Looking around the net I get different values ranging from 25lbs to 35lbs.

Anyone have any suggestions for the right pressure?
 
Peter, Look on the tires side wall it should be listed there.---Keoke
 
30 to 32 front & 28 to 30 rear should be about right. I wouldn't be comfortable with anything as low as 25. Radials need a little more air than bias ply tires to work right.

The pressures marked on the sidewalls are a maximum pressure to be used at maximum tire weight loading which is also marked on the sidewall. This is seldom the case on our cars.

If you really want to get into it, put some chalk marks across the treads, drive it, & see if the marks are uniformly rubbed off side to side. Rubbed off on the sides only usually means under inflated & vs.
D
 
There is no "right" tire pressure for any certain size tire. Much depends on the car it is fitted to. The same size tire made by different companies have different handling characteristics. Changing the tire pressure by a few pounds up or down will also effect handling. The only way to know what's right for your tires and your car is to drive it spiritedly on a twisty road to see how it feels.
Start with a 30 psi test run. Then do a 28 psi run. Then a 32. Also, keep in mind that ambient temperature will change your tire pressures. A hot day will raise the presssure. Hard driving on twisty roads will raise the termperature and pressure.
 
Note tire pressure gauges can vary considerably; I must have a half-dozen of various types--slider, analog/bourdon, and digital--if two agree to their level of accuracy I'm surprised (and none are necessarily absolutely correct since they haven't been calibrated to a standard source or an expensive piece of testing gear). Find a gauge you like that's consistent--I like the digital variety--then experiment with various combinations of pressures, read your gauge and use it exclusively.
 
Last year I invited Josh Pierson to be the guest speaker at a classic rally I organized each year for seven years. Josh is the youngest person ever to drive in the 24 Hours of Le Mans (he was 16!). He said that at that level of competition they adjust tire pressures in 1/10th of a pound increments. Amazing.

Try that on your next club tour in your Healey. "My BJ8 just isn't feeling quite right on right-hand corners ... I think the right rear tire pressure is down two, maybe three tenths of a pound!"
 
I went to 30lbs all around on 165/R15s and no problem with ride or control on my TF. Went to a show Saturday 120 mile round trip, no issues! (y)
 
We have a 62 BJ7 running 5.5 inch wide rims and Vredestein Spring Classic 185/70 HR 15 80 H tyres. We used 30-32 in the front and 28 psi in the rear, based on a whole lot of stumbling around on the Internet. Just an FYI. Doug
 
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