Correct tire pressure???

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I have 195/60/15's on my 99' honda civic si and was wondering what would be the best pressure to run the tires at. The current pressure is at 30#'s front and rear! Thanks!!
 
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Sounds about right to me. What does the owner's manual say? Is the tire pressure shown inside the driver's door near the seat or inside the lid of the console?
 
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Well, the 195/60/15 probably have a slightly higher load rating index, so you could get away with running a couple of PSI less than what is recommended for 195/55/15, but overall, you should be OK with running the same PSI. BTW, why did you end up with an incorrect tire size?
 
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I run my 195/60/15s on my mx6 at 35 psi and it handles a little better but gets much better MPG than at 30-32 psi. A slightly harsher ride, though. Try it and see if you like it.
 
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Which reminds me since we are on this topic, I just got four 195/60QR-15 Dunlop Graspic DS-2 from tirerack.com, can somebody tell me the tire pressure that those tires need to have?
 
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Tire pressure depends on a car, not on a tire, so whatever pressure was recommended by your car manufacturer for summer should be the same for winter.
 
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if your not entirely comfortable with a certain recommended pressure you could always do the chalk test. simply draw a line straight across the tread of the tire. drive it in a straight line for a ways and then check to see where the chalk rubbed off of, obviously if it was more in the center then the tire is overinflated, if more rubbed off on the shoulders then its underinflated, the key is to just keep fiddling with air pressure till the line looks evenly worn off.
 
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Tires make the choice in pressures, not the OEM unless you are replacing with exact OEM replacements. Once you deviate from that, go with what is printed on the sidewall. For most all tires, 32 is a 'safety' number and can be used on pretty much anything passengercar-wise. On LT tires, usually the pressures are higher. I personaly have had great luck with 5lbs under the tires Max printed inflation.
 
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quote:
Tires make the choice in pressures, not the OEM unless you are replacing with exact OEM replacements. Once you deviate from that, go with what is printed on the sidewall. For most all tires, 32 is a 'safety' number and can be used on pretty much anything passengercar-wise. On LT tires, usually the pressures are higher. I personaly have had great luck with 5lbs under the tires Max printed inflation
If that is so, then why are there variations among the same car as to what tires come on the car from the factory? You could buy a civic in Florida that will come with bridgestones, and the civic in Cali will come with Michelin...that would mean different spec'd pressure from the factory? Pressure has to do with load ratings of the tires, the size of the tires and wheels, and what the car manufacturer believes to be the best compramise between a given tire size and the best load capabilty at a particular pressure (given the average load the car will see), as well as ride comfort at that pressure. Many auto manufacturers are now listing two different pressures for different loads; if you look under the fuel flap of any late model VW/Audi, you will see one listed for avg load, and one listed for a full load in the car. The pressures on the sidewall are listed as "MAX inflation pressure;" they never give you a particular pressure to use. Although, to get more load rating out of a tire, you up the pressure.
 
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i feel that midway between the max on the tire and the door will work good. the door gives you the best ride and the tire gives you the best tire life. my door says 32 my tires say 44 and i generally run 35 to 38. in the original posters situation, i fyou do a lot of highway speeds then 32 or 35 might be a better choice. but pressure is dependent on load and speed.
 
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Quote: "If that is so, then why are there variations among the same car as to what tires come on the car from the factory? You could buy a civic in Florida that will come with bridgestones, and the civic in Cali will come with Michelin...that would mean different spec'd pressure from the factory?" Simple Economics. Since most tires are essentially the same in simplicity ( rubber, some tread, sidewall thickness, etc) the numbers printed on the vehicle are a compromise between good ride, OEM tires (which a car is speced' with in the first place) and possible 'substitute tires' in case the originally designed tires are not available. This was one argument between Ford and Firestone, with Ford saying air it up to our stickers' psi, and Firestone saying, 'we made the tires, we know how much air they need. AS stated before, this is why I personally inflate to 5psi BELOW max sidewall pressure. I get a good ride, better gas mileage, and longer wear from the tires.
 
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Where to start? "Tires make the choice in pressures, not the OEM unless you are replacing with exact OEM replacements. Once you deviate from that, go with what is printed on the sidewall." ALL tires of a given size have the same load capacity, regardless of what is printed on the sidewall for maximum pressure. That means that if you are using the same size as OEM, the inflation pressure printed in the vehicle would be applicable. Use a different size, then the vehicle placard is no longer applicable. There is some disagreement as to what is supposed to printed on the sidewall for maximum pressure. There's the Michelin school of thought that says the max load pressure is the answer and then there is pretty much everyone else who says the answer should include pressures for "special conditions". So I don't recommend using what is written on the sidewall for anything except as an advisory of the maximum. "Many auto manufacturers are now listing two different pressures for different loads..." I've only seen this on German cars - the VW group and BMW. I don't think that would qualify as "many", as everyone else lists one pressure. Hope this helps.
 
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Quote: "ALL tires of a given size have the same load capacity, regardless of what is printed on the sidewall for maximum pressure. That means that if you are using the same size as OEM, the inflation pressure printed in the vehicle would be applicable. Use a different size, then the vehicle placard is no longer applicable." This is not neccessarly true, the 'plys' on the sidewall, while the same in amount, can vary in thickness and even with the same amount of air pressure, can vastly effect the way a car handles. To emphasize this, go to your local Pep-boys, buy thier 4-for-$100 4-ply tires, fill them to 32 psi, go drive on a nice curvy road, tell me what you think. Then slip on a good set (of the same size, of course)of name brand (michelin, goodyear, firestone, etc) 4 ply tires, fill to 32psi and tell me there is not a difference. Pressure DOES effect the way a tire operates, and can vary brand to brand. The same size of tire can also have different load ratings despite being the same size. This is even more evident in Motorcycle tires.
 
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"the 'plys' on the sidewall, while the same in amount, can vary in thickness and even with the same amount of air pressure, can vastly effect the way a car handles." Agree, but if we confine our discussion to tires of the same speed rating, the handling differences are not all that great. Besides, I don't think the issue is vehicle handling. "The same size of tire can also have different load ratings despite being the same size." Sort of true, but most P metric tires are standard load, so if we confine our discussion to standard load tires...... Then, tires of the same size have the same load capacity regardless of what pressure is printed on the sidewall, so the inflation pressure printed on the placard would be applicable if the OEM tire size is used - regardless of the manufacturer. Please note that I am distinguishing between P metric (P) and Eurometric (no P) tires. Don't get me wrong, I too use a bit higher inflation pressure, but do it knowing there are compromises in the higher pressure that I am willing to accept. The message I DON'T want to send to anyone who is reading this thread is that the pressure listed on the placard is arbitrary and has no basis in reality and they can use any pressure they want, particularly lower than the placard. In tires, inflation pressure and load capacity are closely linked and underinflated tire failures can have tragic results.
 
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quote:
To emphasize this, go to your local Pep-boys, buy thier 4-for-$100 4-ply tires, fill them to 32 psi, go drive on a nice curvy road, tell me what you think.
This just tells me that they're cheap tires (surprise, surprise), not suitable for spirited driving through twisties. Throwing more air in them is not going to fix them. Actually, I've had plenty of Michelin tires that were also soft as butter and not suitable for spirited driving in the least bit. That doesn't mean a tire with soft sidewalls is a bad tire. Some tires are geared for comfort (soft sidewalls). Others are geared for performance (hard sidewalls). So, I agree with CapriRacer, tire pressure depends on load rating, and not whether I choose Michelin over Watchamacallit. Sure, it's OK to play around with the PSI to some extent, depending on what your priorities are when it comes to driving. [ November 21, 2005, 05:59 PM: Message edited by: Quattro Pete ]
 
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i agree that radials should not be run less than 32 but a lot of hondas say 30, i have even seen explorers say 30. my fiances beetle gives two different pressure depending on load and speed. the low one is 30/29 or so but i always keep them at 32.
 
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