air pressure and dry traction

[novadude]

I have a tire pressure question for you guys....

With a typical all-season radial, if you lower air pressure will it increase the footprint and improve traction on acceleration? I know tire pressure has a significant impact on DOT drag race tires and full slicks, but what about normal street tires? Some information I've seen online seems to imply that lower pressure may help. Also, how low is too low for a typical street radial?

I am asking these questions because I have a new pair of 225/70R15 radials (6" wheel) on a classic car for looks ('65 Nova). Full throttle at WOT in first gear is like being on ice. Seems like everything I find online about air pressure and dry traction (acceleration) mostly pertains to drag radials or slicks, not all-season radials.

Anyone have any tips on how to get a high-powered car on small street radials to hook better?

 

[Jetronic]

I have a tire pressure question for you guys....

With a typical all-season radial, if you lower air pressure will it increase the footprint and improve traction on acceleration? I know tire pressure has a significant impact on DOT drag race tires and full slicks, but what about normal street tires? Some information I've seen online seems to imply that lower pressure may help. Also, how low is too low for a typical street radial?

I am asking these questions because I have a new pair of 225/70R15 radials (6" wheel) on a classic car for looks ('65 Nova). Full throttle at WOT in first gear is like being on ice. Seems like everything I find online about air pressure and dry traction (acceleration) mostly pertains to drag radials or slicks, not all-season radials.

Anyone have any tips on how to get a high-powered car on small street radials to hook better?

Yes it will. But it might never be enough traction to hook up a powerdul car in 1st gear. You might gain about 10% more traction, not double it.

 

[krzyss]

Any modern summer tires in your size?
Why all season?

Krzyś

 

[fdcg27]

I have always found that higher pressures improve steering response.
I don't know about the hole shot part, since I've never had a car with more power than it could put down within reason.
You can burn the tires on the HAH if you try, which I did inadvertently exactly once.
You should also consider the tires that you put on the car.
Some are better than others.

 

[Dr_Dr3i]

On classic cars, which tend to be on the portly side of the scale, I would opt for lower pressures rather than higher. They were made to glide over the road, not feel and telepathically communicate every crack in the pavement to your fingertips.

In a 16" tire, I'd run no more than 30-32 psi for your Nova. Keep in mind that pressures will only go up as you drive and the tires heat up.

+1 on the comment about some tires being better than others. And continuing with the portliness aspect, I'd choose a tire that can handle the extra weight and is known for being grippy, such as summer UHP tires, not all-seasons, since I wouldn't drive it in winter it anyway.

 

[CapriRacer]

I have a tire pressure question for you guys....

With a typical all-season radial, if you lower air pressure will it increase the footprint and improve traction on acceleration? I know tire pressure has a significant impact on DOT drag race tires and full slicks, but what about normal street tires? Some information I've seen online seems to imply that lower pressure may help. Also, how low is too low for a typical street radial?

I am asking these questions because I have a new pair of 225/70R15 radials (6" wheel) on a classic car for looks ('65 Nova). Full throttle at WOT in first gear is like being on ice. Seems like everything I find online about air pressure and dry traction (acceleration) mostly pertains to drag radials or slicks, not all-season radials.

Anyone have any tips on how to get a high-powered car on small street radials to hook better?

I am sure that lower inflation pressure would result in more dry traction

- BUT -

It comes at a price. And one of those prices is the possibility of structural damage.

So I suggest if this car is a daily driver, you get a set of tires whose sole purpose is drag racing and leave the all season tires for their intended purpose - the street.

 

[novadude]

I am sure that lower inflation pressure would result in more dry traction

- BUT -

It comes at a price. And one of those prices is the possibility of structural damage.

So I suggest if this car is a daily driver, you get a set of tires whose sole purpose is drag racing and leave the all season tires for their intended purpose - the street.

Thanks. I do have a set of drag radials on another set of wheels for track use. I was just wondering if there was any way to make my "street" tires work better.

The "street" tires in question are Hankook Kinergy ST H735 with a redline sidewall applied by diamondback classics. There are very few 225/70R14 options on the market, and the Hankooks were one of the few choices could find that were also available in the size I needed up front (185/75R14). I mis-typed 225/70R15 above... these are 14" tires.

BTW... Barry... I LOVE your page! Thank you for putting in the work to share real information on tires.