Anyone played with tire pressure yet on your Dunlop run-flats? I'm running per the Lexux 33 pounds front/back recommendation on the door sticker. If so, what have you experienced in the way of ride quality and handling?

 

Can't help you about Dunlop but my Bridgestone Turanzas run at 32 psi. I know some folks are not enamored with the ride of run flats, but I've been extremely happy so far with the smoothness of the Turanzas.

 

Has anyone put nitrogen in their tires?

 

Since the air is 80% Nitrogen then I guess we all have Nitrogen in our tires. What would be the advantage of running pure Nitrogen? Just don't run Hydrogen however Helium would work and it's readily available and lighter than normal air.. I guess....If are running at high speeds then you can add some pressure up to about 40 something lbs. 32-33 lbs. is a lot plusher though.

Rock

 

For me personally, I haven't totally bought into the nitrogen thing simply because 1. I check my tire pressure often enough, 2. Even though I am concerned with corrosion, I generally sell my rims often enough were it probably wouldn't affect me too much anyway, and 3. On the street too me the benefits simple doesn't matter. On a race car? Well, I can see its benefits.

Supposedly, pure nitrogen has the benefit of being dry. Most air out of compressors (Especially those at gas stations with no inline dryer) contains moisture. My home comressor is probably okay, but I've seen air out of gas station compressor nozzles that leak drops of water. I've shot the air onto my hand and my hand gets wet. In these cases it could be fairly corrosive to the rims in the long run. Also, pure nitrogen molecues supposed to be larger, so in theory it would diffuse less. Now, while independent research has proven that it does hold tire pressures longer which is a good thing, it really only matters to those that don't check their tire pressures at least once a week. Then again, most drivers don't so that could be a good thing after all. Following up on the theory of holding tire pressures longer, that would also mean longer tire life and better gas mileage. Again, this only really matters for those set and forget owners. Also, nitrogen supposed to dissapate heat faster, so you have a cooler running tire and less fluctuation in tire pressure. I have no data, but just to throw out some made up numbers, it could mean the pure nitrogen filled tire increases pressure by 1 PSI rather than 3-4 PSI with compressed air.

Personally, I think the benefit of the nitrogen being dry is probably the only real benefit for street driven cars. I've personally seen many aluminum rims with corrosion on the inner side especially where the tire mounting machines left scratches. For me I don't seek out nitrogen tanks, but if it were free like at Costco and a few other places I would probably use it. I wouldn't pay extra for it though.

 

Interesting thread...
I hope that someone can help shed some light into my questions as well....
If i get aftermarket wheels, are there tire pressure sensors that would work with my car that can be purchased and work with the aftermarket wheels?

Actually anyone know what these pressure sensors look like? A link to a picture would be great.

Thanks in advance.

 

There have been a couple of topics on this. It is possible to use the OEM tire pressure sensing valve stem with aftermarket rims. It just depends if the desgin of the rim will have enough space to accomodate the pressure sensor valve.stem. If I'm not mistaken, some have had success with the GS system on aftermarket rims. Also, I know others with different cars that uses similar valve stem pressure sensors also have had success with it fiting aftermarket rims. However, like I mentioned it depends on the rim and often it will not fit (Not enough room depending on where the valve stem hole is located on the rim itself). Some have used sensor band straps to hold the OEM sensors to the rim itself. This method has been used by some aftermarket pressure sensor companies with good success so there should be no problems.

I don't recall if there has been any pictures posted of the actual system used on the GS, but if you go to Tire Rack and look up the tire pressure sensors, you will see a few pictures of the typical valve stem type and also of the band strap type. That should give you an ideal of what the typically look like and how they mount the different ones.

 

Thanks for the info man...greatly appreciated.

 

Pure Nitrogen does not expand or contract, dependant on air temp as badly as normal air. We tested it some years back and saw about a 20% difference in volume depending on temp. The only really good way to see this outside the lab is during the winter months. When your car has set out in the cold, your tire will look low. Once you drive it awhile, depending on how cold it is, the tires will look fine. Just my .02 worth!

 

This week's Motoweek had good comments on Nitrogen. A Tire Rack rep said good things about using nitrogen and it's availability was moving into the consumer market. The advantages they stated were less fluctuation in pressure and less loss.