Tire pressure vs. handling

[agp423]

How is a car's handling affected when front tire pressure is higher than rear tire pressure or when rear tire pressure is higher than front tire pressure?

[Michael Stoops]

Re: Tire pressure vs. handling

In a nutshell, as you increase pressure in the front tires you decrease understeer, lower it and you decrease oversteer. The opposite is true with the rear tires. This is a great oversimplification, however, as many things will impact understeer and oversteer - trail braking, corner entry speed, camber of road surface, decreasing or increasing radius corner, etc.

There is a ton of great info on this subject at http://www.tirerack.com/tires/tirete....jsp?techid=58

[Eddie6th]

Re: Tire pressure vs. handling

There are many factors involved and it is overwhelmingly complicated. Stick with the manufacturers recommendations,if everything is original.
If your pressures are incorrect,you'll get uneven wear and reduced life.

Most people don't give tire pressures much consideration. The amount of fuel wasted due to low pressures is unbelievable!!! Check it out on the internet.

Just as an example of how precise it is....I can feel a difference in the handling characteristics of my car if I change it by half a PSI.

[the_invisible]

Re: Tire pressure vs. handling

Yeah, OEM spec is probably the best. Many younger people love to increase their tire pressure to stiffen the handling and to create less tire resistence, as to improve acceleration. While this method works, it also places more strain on the stock suspension system.

When upgrading to a more aggressive wheel and tire size combo, you would want to swap out the stock shocks for some heavy duty ones that are damped more aggressively and built with seals that will last longer from the increase stress. The stock bushings may also need an upgrade if the overall suspension setup has been strengthen.

[roushstage2]

Re: Tire pressure vs. handling

On my Roush, I usually run ~ 40PSI up front and 38PSI in the rear. Whether they are set to those specs, or both 38 or both 40, the car still sticks to the road. I do have a full, custom set-up suspension from Roush however. My Neon has trouble handling aggressively for many reasons, tire pressure being the least of 'em, lol. I personally don't see tire pressure being a big factor unless they are far off from where they should be.

[Murr1525]

Re: Tire pressure vs. handling

What can I say... My Dad and I both like about 3psi over the 'door' rating.

[Eddie6th]

Re: Tire pressure vs. handling

What can I say... My Dad and I both like about 3psi over the 'door' rating.

That's a good point. Many vehicles out there have better driveability using different from the recommendation.The manufacturers rec. should be ideal for amount of surface contact,safety and fuel efficiency.

My wheels are different size and tire from original,but when they were factory stock the recommendation in the manual was 32psi. I never liked it and always used 30psi. It was just to 'bouncy'.

It is quite complicated though.You would think two similarly sized vehicles would be the same. But can differ a lot. What you don't see is the weight balance and where it is distributed most. Types of suspension also.

If I compare my '93 civic to an '98 opel Tigra.....both vehicles are 'about' the same length,wheelbase and weight. Both are front engine. The tire pressures are not at all similair.

Where is this thread going? There's more waffle here than a waffle weave

[JD09civic]

Re: Tire pressure vs. handling

Since were on the topic, I have a question. I know that when you drive and your tires heat up the pressure grows higher. Say the door sticker says for my tires to be 32psi, does that mean I air them up to 32psi or do I air it to about 30psi to allow for expansion when the tires heat up? So after I am driving and they heat up the pressure would be around 32psi? Is the door sticker number the pressure you should have before your tires grow or after? Hopefully that's not too confusing. Thanks in advance

[Murr1525]

Re: Tire pressure vs. handling

Usually the door is a cold rating.

[agp423]

Re: Tire pressure vs. handling

It's not for my car, it's for this game Need for Speed Shift...

[Murr1525]

Re: Tire pressure vs. handling

[the_invisible]

Re: Tire pressure vs. handling

It's not for my car, it's for this game Need for Speed Shift...

In that case, the tire pressure settings are blank adjustments... meaning that the adjustments dials on the menu are purely for display

The range of settings are pretty much an on-off function, aka binary code.

Any difference you feel through incremental adjustment is purely psychological

[Eddie6th]

Re: Tire pressure vs. handling

I wonder if there are any detailing games?

Does GranTurismo not have a whizzy car wash....2 second full detail?