Psi????
#1
09-13-2008, 10:34 AM
Psi????
i have a 98 civic ex 2dr lowerd with the stock wheels...whats the psi for my tires? the weather here is warm..its fall...i know they change psi in the winter as well
#2
09-13-2008, 12:45 PM
30 psi all the time the winter the psi changes because the air outside is colder. For every one degree of temperature change will change the tire pressure by 2 psi. Make sure you check your pressure before you drive it like in the morning after sitting all night. Driving the car will cause the tires to get warm thus changing the tire pressure.
#3
09-13-2008, 12:58 PM
one degree temp change = two psi change? I don't know the exact number but that seems like it cant be right. Here the difference between winter and summer can be as much as 100 degrees, which would be a 200psi change by those calculations lol (even if you're talking celcius that seems kinda high)
#5
09-13-2008, 08:26 PM
The best pressure to start with is listed on a sticker in your door jam. Most front wheel drive cars require higher pressure in the front tires because that's where most of the vehicle weight is concentrated. I add 1 or 2 psi to what the door jam sticker lists and wait until the pressure falls 2 psi below that number. That way, I don't have to add air as often.
#6
09-13-2008, 08:34 PM
I wouldnt say most front wheel drive cars require higher pressure in the front. That statement isnt true. "Most" passenger cars run "roughly" 30 psi all the way round
#7
09-13-2008, 11:15 PM
I call BS. It gets down to -40 F in the winter here, and up to 110F in the summer.
Tell me what to set my PSI to in January, and June.
Tell me what to set my PSI to in January, and June.
#9
09-14-2008, 09:34 AM
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most people say go by what it says on the door ajm. only time that really changes is on trucks.... when hauling stuff for obvious reasons 
on stock wheels ill go stock PSI on the door jam sticker. and for my larger 17s ill typicaly go another 2-3psi more..
on stock wheels ill go stock PSI on the door jam sticker. and for my larger 17s ill typicaly go another 2-3psi more..
#10
09-14-2008, 03:59 PM
More info from AA1CAR (Automotive dianostic and repair)
HOW MUCH TIRE PRESSURE?
How much air is the right amount to use? It depends on the application, the vehicle, the size of the tires and how much weight is on the tires. The simple answer is to follow the recommended inflation pressures specified by the vehicle manufacturer. The tire inflation specifications are generally listed in the owner's manual or on a decal in the glove box or door jamb.
For many passenger cars and light trucks, the recommended OE tire pressure may range from 28 up to 34 psi. Recommended pressures for front and rear may also vary, and higher pressures may be recommended for towing or hauling loads.
Keep in mind that recommended inflation pressure are for COLD tires. This means tires that have not been driven on for several hours (ideally overnight). It also means tires that are at a normal outside temperature of about 70 degrees F.
To accurately inflate a tire, you have to compensate for changes in temperature. For every 10 degrees F change in ambient temperature, tire pressure will change a little more than half a pound.
A tire that contains 32 psi of air at 70 degrees F will have a little over 35 psi at 100 degrees F - even if the vehicle has not been driven. Take a quick drive down the freeway and heat up the tires even more, and the pressure may read 38 to 40 psi.
Likewise, when seasons change and temperatures drop, tires lose pressure. They have not lost any air, but the air is not exerting as much pressure as before. The same tire that held 32 psi at 70 degrees F will have only about 28 psi when the thermometer hits 32 degrees F. And when temperatures are in the subzero range, the loss in air pressure will be several pounds more.
Altitude will also affect tire pressure. For every 1,000 feet in elevation above sea level, atmospheric pressure decreases about a half a pound. As a result, tire pressure goes up an equal amount. A tire gauge that reads accurately at sea level will read about 3 psi too high at an elevation of 6,000 feet.
How much air is the right amount to use? It depends on the application, the vehicle, the size of the tires and how much weight is on the tires. The simple answer is to follow the recommended inflation pressures specified by the vehicle manufacturer. The tire inflation specifications are generally listed in the owner's manual or on a decal in the glove box or door jamb.
For many passenger cars and light trucks, the recommended OE tire pressure may range from 28 up to 34 psi. Recommended pressures for front and rear may also vary, and higher pressures may be recommended for towing or hauling loads.
Keep in mind that recommended inflation pressure are for COLD tires. This means tires that have not been driven on for several hours (ideally overnight). It also means tires that are at a normal outside temperature of about 70 degrees F.
To accurately inflate a tire, you have to compensate for changes in temperature. For every 10 degrees F change in ambient temperature, tire pressure will change a little more than half a pound.
A tire that contains 32 psi of air at 70 degrees F will have a little over 35 psi at 100 degrees F - even if the vehicle has not been driven. Take a quick drive down the freeway and heat up the tires even more, and the pressure may read 38 to 40 psi.
Likewise, when seasons change and temperatures drop, tires lose pressure. They have not lost any air, but the air is not exerting as much pressure as before. The same tire that held 32 psi at 70 degrees F will have only about 28 psi when the thermometer hits 32 degrees F. And when temperatures are in the subzero range, the loss in air pressure will be several pounds more.
Altitude will also affect tire pressure. For every 1,000 feet in elevation above sea level, atmospheric pressure decreases about a half a pound. As a result, tire pressure goes up an equal amount. A tire gauge that reads accurately at sea level will read about 3 psi too high at an elevation of 6,000 feet.