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T-Series tire pressure?

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NutmegCT

NutmegCT

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Now that I've got new P165/80R15 radials (all weather, nothing fancy) on the (original steel disk) wheels, I wondered what tire pressure is recommended. Everyday driving up to 50mph, curving two-lane blacktop.

The tires were installed at 30 psi. The original bias ply tires were recommended at 18 psi.

I just took my first drive on the new tires at 30 psi. Just barely turning the steering wheel turns the car faster than I expect. Really sensitive steering, so I'm careful I don't oversteer. Would lowering the front tire pressure reduce that "oversteer" tendency - maybe 24 psi front, 26 psi rear is better for the TD (under 2000 lbs)?

Thoughts?

Tom M.
 
Lower pressure = more friction, more wear.
Just my thoughts.
 
When I last changed the tires on the Spitfire, the garage set them at 32 all the way around. It made for a much harsher, bouncy ride. Not sure if less wear and tear on the tires is worth it
for more wear and tear on me. Reset them to 21 and 26, which is more comfy and I can live with.
 
Thanks gentlemen. I've been googling on and off all day for some way to calculate what psi is advisable, based on weight on the axles, tire size, driving style, etc. Surprised there are so many "just keep trying different pressures until it feels right" replies. Actually surprised so many car guys say "just use what's on the side of the tire". (Yikes! pressure on the side of the tire is *maximum*.)

Funny, but I completely agree with the "keep trying different pressures" suggestion. But at a minimum, that takes a lot of time. You'd think there'd be a way to actually figure a starting point based on weight of car, then adjust up or down from there.

There's got to be some rationale for Nissan labeling "33 psi" for their recent Altima cars, or GM labeling "36 psi" for the Volt.

Thanks.
TM
 
The pressures specified for the original tires are useless for modern radials, and probably even modern cross-bias, classic-car tires.

I'd start at 30 psi, as you have; it should work OK for just about everything. If it seems harsh, try reducing the pressures all around by, say, 2 PSI at a time. Or, if too soft (which I doubt), increase it incrementally. Then, when it seems OK in that regard, you can try experimenting with different pressures front to rear.

It's really not a big deal. If it's too much for you, I'd just set them at 30 psi and leave it that way.

Of course, others who have gone through this exercise with their TDs might chime in with info on the pressures they are using; that might be a better starting point. FWIW, if I remember correctly, I used 28 psi all around on my TD.
 
Of course, others who have gone through this exercise with their TDs might chime in with info on the pressures they are using; that might be a better starting point.
Click to expand...


Exact-a-mundo! Learning what pressure(s) other TD drivers are using - and how they came up with what they chose - would be a great help.
Tom M.

 
My article that I sent you brings up the tire pressures - 18 lbs. was recommended and was ridiculous. To add to the understeer, I would try 25 front and 28 back. Would ride a bit harder but handle much better.
 
Paul - this weekend I used 26/28 and was really happy with the handling. Big improvement, and no oversteer.

Thanks again for the advice.
Tom M.
 
NutmegCT said:
Paul - this weekend I used 26/28 and was really happy with the handling. Big improvement, and no oversteer.

Thanks again for the advice.
Tom M.
Click to expand...

:encouragement: :driving:
 
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