Well I used the search button and ended up with a million different answers, from 40psi to 25psi, the fact is I need to know for a MCS 16inch with usually 1 or 2 people in the car, what's the best tire pressure ? I am using runflats, I am ashamed to say I don't know the exact brand of tires of hand but they are summer and not 4 season tires (I remember asking the dealer for the best he had) well I hope you guys can suggest some numbers that I can put to use.

 

I always keep my tires @ 38psi.

I had 16" (on my previous car), 17", and 18". 38psi seems to be the perfect pressure for me.

 

When you open your door it has the pressure you are supposed to use written in the door jamb. It seems like it is somewhere around 38 psi for runflats but i can't really remember

 

My cars door decal says 30 pounds for normal 2 up driving. 35 pounds for speeds over 100 mph. I run mine at 33 pounds. I have 16" Dunlap runflats.

Disclaimer...Your mileage & tire pressure may vary.

 

See this was my worry I get a 30 to 38psi variable, I want to drive very aggresive in the corners and care more about performance then anything. Should i go with 38psi on Runflat 16inch ?

 

in the summer i run around 33psi. in the fall around 35psi and 37psi in
the near freezing.

 

so if its hot keep the pressure low ? any idea why this is ? all i can think of is the rubber being softer but i dont see how a low tire pressure would increase performance,

 

Like I said go look in the driver's side door jamb. It's right there in black & white showing the tire size & pressure to use. My tires are 17" & the psi is 38 (I went out & lookd in my door). As long as you are running stock sized tires that door decal is gold . If you ever ditch the runflats then all bets are off but it sounds like you are running stock tires. It is my understanding that runflats have a higher psi than regular tires.

As for the person saying 30 psi or 33 if over 100mph I have never used less than 33psi in any tire on any car I have owned & I have doubts that there is any mention of "over 100MPH" on the door decal since that speed is illegal in the USA. So odds are that is a joke post.

 

Pressure increases with temperature so if you set your tires at 30psi when it's 90 outside and then check them when it's 50 degrees, you will see a significant drop in pressure.

I have 17 runflat Dunlops and I follow the door at 30 psi.

Rule of thumb: 1 lb of pressure/10 degrees fahrenheit. So set tires at 30 psi at 70 degrees, then check when 90 degrees outside and they should read 32.

Pressure also increases with tire temp, so driving fast and cornering hard generates more heat, causing pressures to go up. Want proof? Go check cold pressures, drive the car hard (lots of hard cornering), then check pressures while still hot and you will see an increase.

 

I just don't get that Why does my door say 38psi for my MCSC if yours says 30? Is it because I have a slightly heavier convertible? I had Pirelli 17" runflats. That is just odd to me that the recommended pressures would be so different.

 

I could've sworn my door jam said "35psi" for my 17" dunlop summer performance runflats. Hmmm.. now I'm curious and have to go double check.

The tire says right on it "Max pressure 51psi"

At one point (when the car was brand new) my friend and i were filling up the tires (one had gotten low) and, not finding the door sticker, we filled 'em up to 49 thinking that was "just under max" - woops

No harm done, they just slowly leaked air for a while until i realized that 35 was the optimal pressure.

I've noticed that the car seems to corner a little better and handle higher speeds a bit better with around 40 psi, so i generally run between 35 and 40.

(FYI, it's definitely a lot noisier w/ 49psi )

 

Started at 45... that's what the shop used at the time of installation,currently at 36psi

 

Well I'm 500 miles from my car now, but I'm pretty sure it says 30 psi with 17" Dunlop summer runflats.

More pressure will increase fuel economy due to less rolling resistance, but there is an optimal pressure for a balance of ride/handling/economy that the engineers find and specify.

 

You'll find that 33-34 lbs. is a good all around pressure.

 

The only thing I do know is that you aren't supposed to go by the pressure that is written on the tire (I believe that to be the MAX pressure you should ever have on the tire). The tire pressure on the door jamb is what is appropriate for your auto. I am just dumbfounded that we all have such different pressures listed on our doors

 

I see were you are coming from. Too low a pressure & your tires are going to squirm a bit, not what you'd want. But then too much & you start to affect the footprint of the tire. It starts rinding on the middle of the tread & not the whole foot print. Then the tire just slides, not what you'd want either. On the street I run 33 which works out well for me. Two weeks ago I did a track day with pressures set at 35. For me it was perfect & I'd bet that pressure will work for your aggressive style of driving. I hope this babbling by me helps you some.

 

The sticker on your door will be what is appropriate for you car. The pressure should be taken COLD ... not after having been driven a bit.

Just look in your manual ... Your manual will tell you exactly what to use. Some myths here if you believe the manual ...

• Your tire pressure should not change with the seasons ... it has nothing to do with it
• Your tire pressure should not change depending upon how fast you drive ...

The ONLY thing that matters (according to MINI) is how much weight you got in the car.

My manual says 33 - 38 PSI. Now go look up the MAX weight the car is designed for. My car says 816 pounds ... including passengers and luggage. So, if you weigh 100 pounds, 33 pounds is fine. If you got 4 200 pound ppl in there or a lot of luggage, you run 38 pounds.

Its ALL in the manual

BTW, if there is only ONE person driving the car and you consistently run 38 pounds, you WILL wear out the tires the wrong wear ... check out MDSbrains blog. He was running 38 and that was way too high.

When all else fails ... your manual is your friend

 

I beg to differ, but on my cars door jam there is a yellow sticker that says...

IMPORTANT!
OVER 100 MPH
35 Front
35 Rear

High speed running does call for more air pressure in your tires.

 

now that's a load of dog crap right there. next time, measure your
tire pressure at its max operating temps during the different seasons.
the cold temps listed on the car is a starting point based mainly on
load given on a normal ambient temp day (im guessing 55-65F for
normal humans).

your tire pressure in the summer can expand 4-7 psi depending on the
ambient temps, road temps, and how you drive. the target you're
after (if you're a car enthusiast) is to try to get to your ideal
operating psi at the tire's operating average temp.

if the ambient temp is cold and roads are cold, the air inside the
tire will not heat up enough to get to your ideal operating psi, thus
you need to increase your cold psi. vise versa. if you start at a
higher cold psi on a hot day, by the time you reach your operating
temp you are waay past your ideal operating psi.

(this has nothing to do with tires that have lost so much psi that
the sidewalls are heating up due to tire fatigue)

well, that's based on my experience and how i naturally just changed
the settings based on many factors including performance and ride
comfort throughout the seasons. it wasn't really me that determined
to change psi. it was the tires and the car that was calling out for
the change and i just followed. each tire model has its own ideal
pressure setting for different temperatures, so i suggest you play
with your pressures and take measurements during the drive and
while cold and just take a log. im jk about the dog crap part.

 

Wow, well this is allot to take in, after carefull consideration and reading everyones opinions. i believe ill run my tires a 35psi.

 

For this ... and the Crashtons point (BTW, what does your manual say??? Not the door).

Those pressures are COLD pressures. They are intended to be COLD pressures. Thats why, for example, your tire may say maximum pressure 51 PSI to allow for them heating up after high speed runs in the desert.

For example, I was reading about the N type tires for Porsches. They still have cold pressures in what one would call a normal pressure range but after being on the track, the take the tempertures to see and they are, of course, higher.

Another way to look at this is look at your tires after driving. See how they sit on the front. They should be pretty stiff looking (this works best on non RFs).

Then look in the morning, the front end of the car will be lower simply because the pressure is lower. THAT is your cold air pressure and that is the pressure that should be in the 33 - 38 pound range. Not after running hot.

It sounds like to me you think the 33 - 38 pound range is the "ideal range"... while driving. I do not believe thats true. That is the COLD range

Where's MINIHUNE when you need him?

AHH ... wait a sec. So your saying that if the low temp in summer is 70 degrees and the low temp in winter is 10 degrees, the cold pressure in summer will be higher than cold temp in winter and therefore you must adjust..

Got it. Agree with that. But that is still the COLD temp pressure, not the pressure after driving around.

 

I agree that the pressure listed on the door is to be cold tire pressure. That's why my daddy taught me to check my tire pressure when the tires are cold

 

I just looked at my doorjam and it says 35/61 psi for the tires/spare. It also appears that these numbers are added to the pre-existing label with all the other info already stamped into it which leads me to believe, along with the different numbers everyone else has, that these numbers are determined for each car by how its ordered - which model and options and packages that determine the weight of each vehicle.

 

no kidding those are COLD pressures chows!!! :impatient :impatient
gotta get some Vitamin E in your chow.

the list of psi given by MINI is a starting point when you're going
basing on load. not if you're gonna go for your weekend run. that's
a different setting based on your preference and different temps,
driving conditions, etc.

1psi change per 10F.

 

As quoted ^^^ by BAMATT...

When you open your door it has the pressure you are supposed to use written in the door jamb. It seems like it is somewhere around 38 psi for runflats but i can't really remember

THIS IS EXACTLY CORRECT..!!
HOPE THIS HELPS..!!