Tire Pressure for 185/60/14

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velozi

Tire Pressure for 185/60/14

Post by velozi »

What do you like when using this low-profile tire?

I checked mine and they were up to 40psi. Took them down to 36 but want to know what you think is best.
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jfrawley
Posts: 260
Joined: Wed Mar 19, 2008 10:00 pm
Your car is a: 1982 Spider

Re: Tire Pressure for 185/60/14

Post by jfrawley »

I run 195/60/14's at around 28psi. Good grip and decent ride.
John Frawley
Frederick, MD
1982 Spider
http://www.dcfiats.org
RoadRacer

Re: Tire Pressure for 185/60/14

Post by RoadRacer »

Read the manufacturers recommendation on the side of the tire (that is a good place to start).......... My tires say 40 and that is what I keep them at.
velozi

Re: Tire Pressure for 185/60/14

Post by velozi »

Mine said 40 too but I tried 28 and it feels much better.
wengr

Re: Tire Pressure for 185/60/14

Post by wengr »

I think the numbers on the sidewall of tires are just maximum allowable pressures. better to go with the car's owners manual reccomendation.
pope

Re: Tire Pressure for 185/60/14

Post by pope »

40! oh my gosh, you can feel the thickness of a piece of paper on the road at 40. Tire pressure goes with the car, not the tire.

You know that there is a tire out there that will break that rule though, someone will find one a tire that you must follow the manufactures rule on inflation. There is always a rule breaker somewhere, but normally, follow Fiats recommendations.
racydave

Re: Tire Pressure for 185/60/14

Post by racydave »

The pressures listed on the tire were used to rate the tire and not meant as a guide for street use. The ownwes manual for my 79 says 26, I run at 28 8)
RoadRacer

Re: Tire Pressure for 185/60/14

Post by RoadRacer »

racydave wrote:The pressures listed on the tire were used to rate the tire and not meant as a guide for street use. The ownwes manual for my 79 says 26, I run at 28 8)
Tire manufacturers recommend using stated psi for maximum performance of their specific tire. Fiat recommends 26 psi for the specific tire they put on. If the tire says 40 psi and you use 25 psi, the tire is not wearing the way the tire engineers designed it to wear. Some tires recommend 26 some 36 some 40 of the same size. So we are not talking apples to apples
when we say Fiat says to use 26 psi and I just bought these performance tires that recommend I use 40 psi for maximum performance and ware.......
pope

Re: Tire Pressure for 185/60/14

Post by pope »

On passenger cars, use the inflation rate on the door of the car. Tire manufactures do not know what car that tire is going on and how heavy the car is. Car Manufactures know and tell you. I dont know how this misinformation on tire pressure being on the tire started, but it is an urban legend. Please go to ANY tire web site or tire dealer and they will tell you to follow the cars rated pressure, assuming that you are using the same size tire.

If you don’t know the proper inflation air pressure for your tires, what do you do?
Easy. Check at one of the following places on your vehicle:
In the vehicle owners manual.
On the vehicle’s door jamb. (Often, a vehicle information placard is located on the door jamb along with the recommended tire inflation pressure.)
Inside the fuel hatch filler flap. (In some vehicles.)
The glove compartment door. (In some vehicles.)
But NOT on the tire. The inflation pressure shown on the tire sidewall is only the maximum tire inflation pressure. In most situations, the vehicle manufacturers recommended tire inflation pressure is shown on the vehicle placard.

You can adjust a couple of psi depending if you are driving on long or short trips.
RoadRacer

Re: Tire Pressure for 185/60/14

Post by RoadRacer »

OK, I stand corrected :? Here is a link to correct tire pressure :D

http://www.tirerack.com/tires/tiretech/ ... p?techid=8
evm1024
Posts: 85
Joined: Tue Feb 05, 2008 12:33 am
Your car is a: Pininfarina Spidereuropa 1983

Re: Tire Pressure for 185/60/14

Post by evm1024 »

To me both answers feel to be rules of thumb rather than exact results. I am presuming that the correct tire inflation would result is even tread wear. So to get the correct inflation we would need to see a set of graphs of wear patterns based on weight per tire vs inflation.

For example: at 500 pounds per tire 28 psi is under inflated, 30 pis even wear, 32 psi over inflated. And so on for other weights per tire.

This is I imagine quite complex as that the temp of the tire changes with use and thus inflation as well as the actual use of the tire (Hwy vs track) and getting the correct inflation is difficult.

I wonder if we could inflate a cold tire to some pressure, run it around to running temp for the type of drivinng we typically do and then spray a band of paint on the tread and run it straight for a short distance to see the wear pattern. Much like reading plugs....

This sounds like a lot of work and just using the recommended inflation might just be close enough.... I wonder if all tires are built a standard inflation. That is to say that they are all engineered so that at 500 pounds load and 100 degrees internal temp, 28 psi gives a flat tread wear pattern.

Regards, Ethan
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