Tire pressures for Road trip

[boss2k]

Just filled them up at 33 Cold psi. .how much shud they be during Road trip ? Should they be less than 32 for a smoother ride?

[Brasko]

Originally Posted by boss2k

Just filled them up at 33 Cold psi. .how much shud they be during Road trip ? Should they be less than 32 for a smoother ride?

I've been experimenting with this for my upcoming road trip as well as daily driving and track days.

This is the method I follow:

1. Drive car several miles to get tires up to temperature.
2. Park vehicle and use a quality digital tire pressure gauge to check pressure. I use a Michelin tire pressure gauge.
3. Adjust pressure as needed so that all tires are at equal pressure.
4. Drive vehicle a few miles to get tires back up to temperature.
5. Compare results with onboard tire pressure monitor.

Ultimately, you would want to balance the tire pressure so that when the vehicle is under load, the tire air pressure remains as equal as possible. For instance, my current set up is the following. This allows room for extreme cases (long road trips, spirited driving, etc.) were the tires are building heat and the air pressure rises to remain under or at the 51psi max pressure recommended by the Continental Tires.


Right front tire: 47.6psi
Right rear tire: 47.3

Left front tire: 47.9psi
Left rear tire: 47.6


Looking at these values you can see that when my M3 is at load the tire pressure remains pretty equal with the lowest value (right rear) 0.3psi under the average value versus the highest tire pressure (front left) at 0.3psi over the average. The added weight from the driver (myself) accounts for the variance. Some fine tuning might bring these values even closer.


**These examples are based on an F80 M3 with a driver at 5'10, 165lbs. Full tank of gas, and no other cargo. Wheels are 19" with OEM Continental Tires. Your experience may vary.

[boss2k]

Originally Posted by Brasko

I've been experimenting with this for my upcoming road trip as well as daily driving and track days.

This is the method I follow:

1. Drive car several miles to get tires up to temperature.
2. Park vehicle and use a quality digital tire pressure gauge to check pressure. I use a Michelin tire pressure gauge.
3. Adjust pressure as needed so that all tires are at equal pressure.
4. Drive vehicle a few miles to get tires back up to temperature.
5. Compare results with onboard tire pressure monitor.

Ultimately, you would want to balance the tire pressure so that when the vehicle is under load, the tire air pressure remains as equal as possible. For instance, my current set up is the following. This allows room for extreme cases (long road trips, spirited driving, etc.) were the tires are building heat and the air pressure rises to remain under or at the 51psi max pressure recommended by the Continental Tires.


Right front tire: 47.6psi
Right rear tire: 47.3

Left front tire: 47.9psi
Left rear tire: 47.6


Looking at these values you can see that when my M3 is at load the tire pressure remains pretty equal with the lowest value (right rear) 0.3psi under the average value versus the highest tire pressure (front left) at 0.3psi over the average. The added weight from the driver (myself) accounts for the variance. Some fine tuning might bring these values even closer.


**These examples are based on an F80 M3 with a driver at 5'10, 165lbs. Full tank of gas, and no other cargo. Wheels are 19" with OEM Continental Tires. Your experience may vary.

After doing this do you store the tire pressure for TPMS, at what point of time do you store for TPMS?

[Brasko]

Originally Posted by boss2k

After doing this do you store the tire pressure for TPMS, at what point of time do you store for TPMS?

Not exactly sure what you mean by store the TPMS? The Michelin tire pressure gauge allows you to record the front and rear air pressure independently so you can always reference that or adjust the recording when you want.

[boss2k]

Originally Posted by Brasko

Not exactly sure what you mean by store the TPMS? The Michelin tire pressure gauge allows you to record the front and rear air pressure independently so you can always reference that or adjust the recording when you want.

when you adjust tire pressure you need to store it in the idrive for the system to update the tire pressures so that it can warn you for low/flat tire. its not an intelligent system but the sensors work based on what you store.

In my Acura i never have to store tire pressure for TPMS, the sensors automatically active when the tire pressure falls below the set limit.

[Racer20]

For street use, set your tire pressures to the recommended pressure in your owner's manual. Set them as close to 70deg ambient temperature as possible, when the car hasn't been driven in a while.

[boss2k]

Originally Posted by Racer20

For street use, set your tire pressures to the recommended pressure in your owner's manual. Set them as close to 70deg ambient temperature as possible, when the car hasn't been driven in a while.

I set them when tires are cold, very 1st thing in the morning.