Just posted on another tire-pressure thread earlier tonight. Maybe I should shut up. . . . Naw.

There are middle grounds. 30 is ridiculously low; 60 is ridiculously high. 50 is a little too high for my blood. 44 is nice. Why not just do the max cold inflation number on the sidewall?

Regarding if someone on the internet jumped off a cliff (many posts ago): what cops do with their tire pressures is true. My brother and dad are both Montana Highway Patrol, running Impalas and Crown Vics up there. Having been to their share of driving schools, they swear by inflation in the 40s over inflation in the 30s any day of the week, and they inflate to 42-44. (That's max cold inflation in their case, because they run speed rated tires one notch higher than the limiters on the cars, as they're above 110 miles per hour with some regularity).

Their rationale is explicitly improved handling. (God knows, driving those boats with all that extra gear, they need it.) Their driving schools tell them there is absolutely no downside to running max cold pressure except harsher ride. Not in wear, handling, economy, anything.

Cheers --
doug

 

I think we can all accept that police trainers and experienced officers recommend filling their tires to at a minimum 42psi up to 50psi.

At the same time, experienced SCCA drivers recommend 40psi for autocross driving of the Civic and other small cars on the stock tire sizes.

So if you choose to run your HCH tires at 50psi, are you saying that you trust the police recommendation more than the racer recommendation? Or do you recognize both are legitimate, but feel that your car and driving style has more in common with the police than with the autocross drivers? Or is it that you feel the police recommendation shows that 50psi is safe enough and you want the best FE possible?

I'm just trying to understand the thought process.

 

Be that as it may, my remark was provoked by Nash quoting an opinion piece. Anecdotal evidence over the net isn't a reliable thing. Even some of the rules of thumb our parents or guardians told us are no longer applicable. Had Nash quoted the safety & maintenance documents that many tire manufacturers post on their web sites, then that would have made for a good statement. They know their product and are an authoritative reference, not the second-hand wisdom of a user, even if it's a member of the police force (assuming the he is).

We all have our filters, and we respond with less than what we're given. This gets to be a problem if the advice given is a couple generations removed from the source. I certainly feel that resetting a topic of discussion like this (filling in some of the missing arguments in favour of moderate-to-minimum tire pressure) and jarring people out of their complacency would inspire them to check into things for themselves. We're swimming in information with direct access to the manufacturers.

 

Once again Msantos is right -- esp about beating a topic to death.

From the tirerack -- you guys trust them?

http://www.tirerack.com/tires/tirete...e.jsp?techid=1

Disadvantages of Overinflation

An overinflated tire is stiff and unyielding and the size of its footprint in contact with the road is reduced. If a vehicle's tires are overinflated by 6 psi, they could be damaged more easily when encountering potholes or debris in the road, as well as experience irregular tread wear. Higher inflated tires cannot isolate road irregularities as well causing the vehicle to ride harsher and transmit more noise into its interior. However, higher inflation pressures reduce rolling resistance slightly and typically provide a slight improvement in steering response and cornering stability. This is why participants who use street tires in autocrosses, track events and road races run higher than normal inflation pressures.

 

I trust them to find the right tires for my car, then mount and balance them. I do not trust them to understand the engineering that goes into a tire.

 

Bottom line is we are not qualified to say what is a safe max tire pressure. Only the those that make the tire are. If the sidewall says 44 psi max then 44 is as high as you should go for safety reasons. The auto companies say 32 psi because it makes their cars feel so soft and cushy going down the road and people wont complain about the stiff ride on the new car they just bought.The car companies are biased in the psi recommendations the same way oil companies are bias in the 3mo.or 3000 mile oil change. The sooner you change oil, the more money they make selling more oil. The car companies, who aren't in the oil selling business , tell you to change your oil much less often, unless heavy towing is involved...Trust the ones who made the dang tire and stay at 44 psi or less. I use 42 on mine. It's their call, they are the educated ones who went to Tire College, Haha

 

Are the tire pressures recommendations that are being referred to in this post specific to winter or summer, or is everyone referring to year round tire pressures?

 

Tirerack would like to sell you more tires....

 

I've always ran max pressure in the ~14 cars I've owned since 1978 and not had any problems what so ever. I've had one pothole blow-out about 20 years ago on a tire known to have lower pressure. (Probably under inflated)

My HCH came with the Dunlops and I ran them @ 51PSI for the life of the tires, which lasted 88,000 miles. They were rotated every 15K and had an alignment every 20K miles. They wore evenly across and had excellent cornering traction.

Max pressure have always worked for me, but I also understand there are other opinions. I gain around 7MPG in my HCH of 32 vs 50lbs.