: How to get the V to accept a higher tire pressure?



silver02stang
05-27-09, 03:21 PM
The tires I'm runnin' now have a max psi of 51psi. i'd like to have 'em set to 41-45psi but as soon as i drive a block the tires heat up and anything over 41psi sets off the warning on the dash. Is there any way to get the system to accept a higher PSI before warning?

Eric Pittman
05-27-09, 03:50 PM
The tires I'm runnin' now have a max psi of 51psi. i'd like to have 'em set to 41-45psi but as soon as i drive a block the tires heat up and anything over 41psi sets off the warning on the dash. Is there any way to get the system to accept a higher PSI before warning?

Just curious... what are you doing that you want that sort of PSI? I have never tried going over 35 warmed up...

silver02stang
05-27-09, 04:53 PM
the stockers... and a lot of aftermarket tires max @ 41psi. i like a firmer ride. i like to set mine a bit higher... 41-43 cold - as long as the pressure is below the tires max (which my max is 51)

SkullV
05-27-09, 04:55 PM
Isn't the max just the maximum pressure you can use to seat the bead on the rim? I wouldn't try and run anywhere close to the max for everyday driving. Most passenger cars should be set from 32-35 cold and trucks should be 35-37.

whisler151
05-27-09, 05:04 PM
I have a TPMS Sensor on the fritz and my dealership wouldnt replace it because I had my tires set to 40psi. They said that is too high for the system. I am running 245/40 and 275/35 and Tire Rack told me to keep them at 40psi because they are lower profile than stock.

I am back to 30psi cold.

YoshiV
05-27-09, 06:03 PM
At that pressure level all you're gonna do is wear out the center treads of the tire real fast!

ctsv154
05-27-09, 06:07 PM
Depends on the tire width, the wheel width, the aspect ratio, the thickness of the sidewall, the stiffness of the sidewall, the average load the tire will see. All this determines proper tire pressure. Some tires like a lot of pressure some are happy with very little.

heavymetals
05-27-09, 06:13 PM
Best way a friend of mine and I came up with is to remove all the TPMs and stick them in a vessel and pump it up to 35 lbs ands carry it in the trunk or rear seat.

If you can't raise the bridge, lower or remove the river. :rolleyes:

ctsv154
05-27-09, 06:17 PM
Best way a friend of mine and I came up with is to remove all the TPMs and stick them in a vessel and pump it up to 35 lbs ands carry it in the trunk or rear seat.

If you can't raise the bridge, lower or remove the river. :rolleyes:

Clever

DisposableHero
05-27-09, 06:28 PM
I have mine set around 40 cold too and it's pissing me off always dinging.

I want mine set higher for less rolling resistance thus better mpgs.

stkshkr
05-27-09, 06:29 PM
Best way a friend of mine and I came up with is to remove all the TPMs and stick them in a vessel and pump it up to 35 lbs ands carry it in the trunk or rear seat.

If you can't raise the bridge, lower or remove the river. :rolleyes:

Why not just wrap them in aluminum foil and put them in the basement, you'll have dashes and you can't go into comp mode for about 50-75 miles, after that everything works fine.

Q. How do I find the correct tire pressure for my car?

A. There’s a pressure rating on the tires themselves, but the door has a different pressure number. Which one is correct? How many psi should I have in my tires?
Having the correct tire pressure is extremely important for getting good gas mileage and the most life out of your tires. Your car has a specific tire pressure that will give the best gas mileage, handling and tire life for that car, and it’s written right on the door of the car. That’s the one you should follow when filling up.

On newer cars, the recommended pressure is most commonly listed on a sticker inside the driver’s door. If there’s no sticker on the door, you can usually find the specs in the owner’s manual. Most passenger cars will recommend 32 to 35 psi in the tires when they’re cold. The reason you check them cold is that as tires roll along the road, friction between them and the road generates heat, increasing tire pressure. For the most consistent tire-pressure reading, make sure the car has been sitting overnight, or at least has been parked for a few hours.

Do not inflate your tires to the pressure listed on the tire itself. That number is the maximum pressure the tire can hold, not the recommended pressure for the vehicle. Tricky, huh?

Over-inflating your tires will give you a bouncy ride and an ill-handling car and affect braking performance, while under-inflated tires can develop premature wear from increased friction. Either way, not having your tires at their recommended pressure will negatively affect tire wear, gas milage and vehicle performance.

CIWS
05-27-09, 06:36 PM
What about No2 and filling them to around 38psi just to keep the temp variance down?

DILLIGAF
05-27-09, 08:22 PM
How bout getting some 10 plys and just ignore the dash warning?Car should ride awesome!

silver02stang
05-27-09, 08:39 PM
oofta... this is way more tire info than i was expecting!

so. if i'm reading this correctly - i'm to completely ignore the psi # on the sidewall of my tire and only go with what is on the door. Do tire sizes, rim widths, etc., etc., have no bearing what-so-ever on what pressure i should be running? Where would i get the ABSOLUTE truth to what pressure i should be running? The tire manufacture and the manufacture only?

Scatillac
05-27-09, 10:13 PM
What about No2 and filling them to around 38psi just to keep the temp variance down?

That's what the shop put in my PS2s (at 36 lbs) when they were installed and it is a bit more stable than air but still varies by ~2 lbs.

rand49er
05-27-09, 10:37 PM
I put nothing but 79% N2 in mine. :rolleyes:

DILLIGAF
05-27-09, 11:28 PM
We have no clue what tire your using.Me,I have Falkin 452"s,run them at 30psi cold,they will get to 34psi hot.No alarms here,I have no clue as to why you would want stiff ass tires on your car.This is a hot topic over in the Prius forums.

UnsafeAtAnySpd
05-27-09, 11:33 PM
On my Goodyear Eagle RSAs I get 29 PSI cold and 43 PSI hot. That seems like a huge variance, right?

DILLIGAF
05-27-09, 11:37 PM
You have crappy tires IMO

bpitas
05-28-09, 03:31 AM
The best way to tell what pressure you should be running is to use an infra-red thermometer on the tires after you've been running them at a decent speed. You've got to measure it quickly though before they cool off.

If you're running your tires that high cold, I can guarantee you they will be 10 degrees hotter in the center of the tread, and will wear out really quickly. Not only that ,your handling is probably going to suck because your contact patch will be smaller (only the center of the tire) until the center wears away.

You can't go by what's on the door either unless you're running the exact same tire as original. For example, our cars originally came with F1 supercar runflat and said 29 or 30 psi. But runflats have a significantly stiffer sidewall so they don't need to be inflated as much. You wouldn't necessarily want to run non-runflat tires that low or you'd get premature wear on the edges, and you'd potentially roll over the sidewall...
What I do is on a really hot day I let them get over 42 so it starts beeping, and then I use a pressure gauge that allows me to release air to get all 4 tires down to around 40 psi *hot*. It's weird but you can set the tire pressure even across all four tires cold and when they heat up you will see corner-to-corner variance, but if you equalize them all *hot*, they seem to be equal whether they are hot or cold unless you're cornering or one side is in the sun. You just have to make sure to check them when you've been going straight and level, no hard braking or acceleration, and make sure there isn't one side in the hot sun. My tires are around 31 psi cold. More than that and they go away very quickly - especially the rears for some reason. ;-)

CIWS
05-28-09, 10:18 AM
On the STS-V the recommended pressures are 30 front and 32 rear (cold). I ran that with the OEM tires (Pirelli run flats) and the center was wore down by 8K miles like it was over inflated (common among the owners). The new set of tires I ran for the first few thousand and the same started occurring. So I've switched to running the rears at 30 PSI and the fronts at 32 to keep the wear even.



The PSI numbers on the tire's sidewall are usually only a max pressure number, not close to where they should be run at. As others have already stated there are various factors to consider in ride, handling, and wear when determining where to run your tire's pressure on a given car.

-T-
05-28-09, 10:31 AM
Don't listen to half the BS on here about what PSI your CAR wants. It has everything to do with the tire for air pressure.

You should be within 5-7 Psi of the max tire pressure for proper wear of tire tread. I had this same problem, i just learned to live with the frequent warning until i pull the sensors when i change my tires. If you are running around at 35-40 Psi on a 51 max Psi tire, you will have excessive outer tire wear. If you are at or very near max tire Psi, with no extreme load on the tire, you will have excess center tire wear. This also depends on tire size that is on your stock rim. If you are stock tire size and stock rim... 5-7 Psi of max tire. If you have over-sized tires on the stock rim... a tire shop or alignment shop can check for a flat footprint and let you know what Psi to run at.

If anyone on here has ever owned a truck used frequently for hauling high loads, they know about tire pressures and tire loads. If you are that unsure about it, call your local tire shop. They should be more than happy to assist.

Rey
05-28-09, 12:07 PM
Tire pressure settings will remain a matter of opinion. Most of us who have changed air pressure from that on the door sticker have researched the issue, and are satisfied with the results of their research. Nevertheless, one cannot "go wrong" using factory-recommended tire pressure settings. My own experience running at 40 psi cold in several vehicles for hundreds of thousands of miles over many years has been favorable - no adverse tire wear that I can tell. My tire pressure has never exceeded sidewall maximum when hot driving - I do monitor this.

The question asked was not what is the optimum tire pressure, but rather how does one reset the tire sensors so they do not "beep" when tire pressure exceeds 42 psi. My source at TPIS asked the same question and tried to find the settings within the ECU. They are not there. It is an FM radio signal to the radio, which in turn trips the dash alert. My sense is that one would have to hack into the radio itself to alter the scope of the alert.

-T-
05-28-09, 02:27 PM
Tire pressure settings will remain a matter of opinion. Most of us who have changed air pressure from that on the door sticker have researched the issue, and are satisfied with the results of their research. Nevertheless, one cannot "go wrong" using factory-recommended tire pressure settings. My own experience running at 40 psi cold in several vehicles for hundreds of thousands of miles over many years has been favorable - no adverse tire wear that I can tell. My tire pressure has never exceeded sidewall maximum when hot driving - I do monitor this.

The question asked was not what is the optimum tire pressure, but rather how does one reset the tire sensors so they do not "beep" when tire pressure exceeds 42 psi. My source at TPIS asked the same question and tried to find the settings within the ECU. They are not there. It is an FM radio signal to the radio, which in turn trips the dash alert. My sense is that one would have to hack into the radio itself to alter the scope of the alert.

There should at least be some parameters that can be edited. I am assuming this because you cannont go into COMP mode unless these parameters are met. Surely there is something in the ECU that can be over-ridden or edited.

CIWS
05-28-09, 02:36 PM
If you are running around at 35-40 Psi on a 51 max Psi tire, you will have excessive outer tire wear.

This is simply not a true statement, as proven in one instance with my stock rear tires. They were run at the Cadillac recommended pressure of 32 PSI cold and still wore in the center as if they were over inflated. Their max pressure rating is 51 psi. This is a common problem with that tire (Pirelli Eufori) on the STS-V. The fronts wear fine running at 30-32 cold.

It varies with the tire and load.

DILLIGAF
05-28-09, 07:08 PM
This tire discussion is tired already.Why the f did you buy a V and worry about tire wear?I'm at 49,000 miles and have had 6 sets of tires,2 of the sets were run flats!Buy your self some Falkiins,very stiff sidewalls,no crazy temp variations,great performer!Have some fun dude life is short.

Eric Pittman
05-28-09, 08:58 PM
This tire discussion is tired already.Why the f did you buy a V and worry about tire wear?I'm at 49,000 miles and have had 6 sets of tires,2 of the sets were run flats!Buy your self some Falkiins,very stiff sidewalls,no crazy temp variations,great performer!Have some fun dude life is short.

Agreed. :lildevil:

silver02stang
05-28-09, 08:59 PM
soooooooooooooooooooooo. to refer back to my original question...

Does anyone know how to reset the tire pressure gauges? I'm perfectly comfortable figuring out what tire pressure I would like to run at... Regardless of popular opinion, I will be runnin' higher than 41psi. Its just annoying to constantly see the warning. Is there a way around this? ...short of putting them in a pressure chamber :)?

silver02stang
05-28-09, 09:03 PM
This tire discussion is tired already.Why the f did you buy a V and worry about tire wear?I'm at 49,000 miles and have had 6 sets of tires,2 of the sets were run flats!Buy your self some Falkiins,very stiff sidewalls,no crazy temp variations,great performer!Have some fun dude life is short.

i didn't mention anything about tire wear or mileage. i did however mention that higher psi was my preference. for someone that is getting their undies in such a bundle over this topic - why don't you just avoid this thread and keep your comments to yourself? :annoyed:

DILLIGAF
05-28-09, 09:37 PM
i didn't mention anything about tire wear or mileage. i did however mention that higher psi was my preference. for someone that is getting their undies in such a bundle over this topic - why don't you just avoid this thread and keep your comments to yourself? :annoyed:No panties in bunch here,air them suckers up way high make your car ride and handle like shit.:bouncy:

The warning will never go away
Might want to check what the wheel psi rating is
Didn't mean to piss you off

This subject has gone on for years in here,mostly drag racers,track day guys who are searching for the perfect handling and traction,I believe your the first who just likes over inflating your tires for no reason.

ctsv154
05-29-09, 07:52 AM
soooooooooooooooooooooo. to refer back to my original question...

Does anyone know how to reset the tire pressure gauges? I'm perfectly comfortable figuring out what tire pressure I would like to run at... Regardless of popular opinion, I will be runnin' higher than 41psi. Its just annoying to constantly see the warning. Is there a way around this? ...short of putting them in a pressure chamber :)?

As stated by somebody in here, just remove them and install regular valve stems. Dont keep them near the car or if you do, story them in foil. The car will not see them and you will have dashes and you can do what ever you want. For about 100 miles or so, the car wont go into comp, or turn all the way off but if you wait until you get dashes on all four corners, the car will then go back into those modes and you can have your tires at 80psi and the car will never now the difference.

I have sensors in, I just never programed them yet and this is how my car reacts as well.

CIWS
05-29-09, 08:06 AM
:yeah:



This tire discussion is tired already.Why the f did you buy a V and worry about tire wear?I'm at 49,000 miles and have had 6 sets of tires,2 of the sets were run flats!Buy your self some Falkiins,very stiff sidewalls,no crazy temp variations,great performer!Have some fun dude life is short.

Just don't want them wearing uneven and have to be changed before the whole tire is worn out :D


soooooooooooooooooooooo. to refer back to my original question...
I will be runnin' higher than 41psi. Its just annoying to constantly see the warning. Is there a way around this? ...short of putting them in a pressure chamber :)?

Like has already been said, remove them completely from the car and away from the ECM. After some mileage point (50-100) the car will ignore their absence and you can do as you wish.

SuperVeee
05-29-09, 11:01 AM
“Regardless of popular opinion, I will be running' higher than 41psi”
From a traction standpoint it just doesn’t make any sense to me to over inflate the tires. Plus in the rain it can get pretty dicey with too much air.


“i like a firmer ride”
You can provide a firmer ride with firmer shocks (and or springs) with out compromising your safety or the handling of the car.


“I'm perfectly comfortable figuring out what tire pressure I would like to run at." “i did however mention that higher PSI was my preference.”
Since you do not know me and this is the internet - I recommend you take your car to a local autocross and try running with 32 lbs vs 42lbs. See how the car behaves (oversteer and understeer) and note your best times. This is an easy and fun way to test. Who knows - your high PSI preference may change….

silver02stang
05-29-09, 08:13 PM
“Regardless of popular opinion, I will be running' higher than 41psi”
From a traction standpoint it just doesn’t make any sense to me to over inflate the tires. Plus in the rain it can get pretty dicey with too much air.


“i like a firmer ride”
You can provide a firmer ride with firmer shocks (and or springs) with out compromising your safety or the handling of the car.


“I'm perfectly comfortable figuring out what tire pressure I would like to run at." “i did however mention that higher PSI was my preference.”
Since you do not know me and this is the internet - I recommend you take your car to a local autocross and try running with 32 lbs vs 42lbs. See how the car behaves (oversteer and understeer) and note your best times. This is an easy and fun way to test. Who knows - your high PSI preference may change….

thanks for the input. the pressures im asking about would be for daily driving. as far as competitive driving goes - the pressure would vary depending on what would be best for the type of driving i'm intending to do.

i'm the only person i know that can get almost 55k miles out of a tire with a 300 treadwear rating. with the tires warm, i set 'em about 6-8 psi short of the max. i've NEVER had any kind of problem in the rain or otherwise and my tires have always worn nice and even.