how often do you put air in your tires? and do you follow the recommended tire pressure that is located on the doorsill of the car?

sorry for the noob question.... i just got a boxster s 4 weeks ago.

the temperature here in NJ has been changing a lot. Ive got air in the tires maybe 2 weeks ago at the dealership and the car drove a lot better!

but im thinking maybe i need more air again... drives a little sluggish.

How do you know when to put in air or not?

 

Monthly is good, some people do it every tank of gas. And nitro-fill is NOT and excuse to blow off checking your tire pressures.

I'm lazy, I rarely check mine...

 

I usually check mine before I go for a drive that will be brisk.

But saying that, I've only had to air in them once. I have 21k on the clock.

 

Establish a routine, I check my tire pressure EVERY Saturday morning, while it is still cool and the cars have sat overnight.

It will save you in the long run!

YES, use the recommended pressures on the sticker in the car door sill.

 

What tire pressure do you use with aftermarket wheels/tires? for example do I use the same recommended tire pressure even though I went from 17's stock to new 19's?

 

This will depend on the load rating of the new tires. In my experience, most aftermarket tires with a lower profile sidewall will require higher pressure for the same load rating.

For example, one of my daily drivers had 185/70/14 93s and a stock recommended pressure of 28psi. The max inflation for this tire wass 35psi with a max load of 1433lbs. If the load decreases linearly, then the load at 28psi was 1146lbs.

When I changed to 215/45/17 88v, the max load rating is 1235lbs at 44psi. So calculating that I need a load capacity of 1146lbs, I needed to inflate the tires to 41psi.

This assumes the load rating is linear, which it probably isn't. But I haven't had a tire blow out due to overloading, so it must work pretty well.

Somebody correct me if this is completely wrong and I've been risking my life for years now.

 

Something as simple as checking air pressure suddenly is not so simple!

 

That's what happens when you change tires from stock. And with all the choices out there, that's not too simple either, lol.

 

Nitrogen is more consistent across temp ranges & leaks less. Still needs to be checked though.

 

Nitro. For me it's about extending the life of my tires.

 

I can check mine anytime even while driving. Mine has a readout on my instrument panel which shows pressure at each corner to 1 PSI. I have checked it against my hand gage and seems to be very accurate.