how much air pressure in your tires

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My skinny fronts get 32 just because of the load they bear, the rear N50s keep right around 22 for the best patch on 8" rims.
 
how much do you think the air pressure contributes to ride quality?
..say 32 psi to 26 psi?
 
On my 68 S-clone,I run 28/29 in the 235/60-14 frts and 24 in the 295/50-15s. This is for even treadwear. Very nice ride.
Bit soft on the turns, til the suspension takes a set on the bump stops. The sidewall roll-over isnt too bad.Once in a while, I pump the fronts up to 32 and go have some fun. But the current tires arent sticky enough to make much of a difference.
At 22 the rear feels odd on turns.The front rides nice at nearly any pressure. Modern radials are awesome.

"how much do you think the air pressure contributes to ride quality?
..say 32 psi to 26 psi? "
Not nearly as much as Lightweight wheels, and decent shocks.When a rear goes down on my car I can tell almost right away. But until the fronts are down to 20-24, I dont notice the fronts going soft.So I'm assuming that means not much change in ride quality from 29 down to 24.
When I had skinnier tires on the back, I noticed ride quality more easily.
 
I run it per what the tire load is rated for and adjust based on the ride feel.

For example lets say all 4 tires have a load rating on the sidewall that shows a max load of 1200 lbs at 50 psi.

Well assume that the car weighs around 3000 lbs and for purposes of simplicity lets say it has equal weight distribution front and rear.

That means that your car has 1500 lbs on the front tires and 1500 lbs on the rears.

Since you have 2 tires on each end you divide the weight by 2 so 1500 lbs/2 = 750 lbs on each corner. Once again this is assumption and the accurate way to do it would be to weigh each corner.

Moving on, if you divide the weight of the corner by the weight rating of the tire you get a ratio.

750 lbs per corner/1200 lbs max weight rating = .625 lbs

Multiply that ratio by the max inflation rating on the tire and you get the psi for the tires based on the weight of your car at that corner.

50 psi max rating x .625 = 31.25 psi. per tire MINIMUM.
This is the math that my tire buddy taught me. (Owner of tire shop for 30+ years) I know that pressures can be adjusted according to particular needs so this is just a baseline but it's a great place to start and adjust from.

Ultimately it's your decision based on how the car feels and handles that will set the exact psi you will desire.
 
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