Say a tire is labeled xxx pounds at 44 psi or 50 psi max - what is the absolute max I can put in the tires for MPG? I want to push the limit as hard as I can. I don't care about ride or even the best grip. What's the safety factor?
Absolute MAX tire pressure..............
- Thread starter Pablo
- Start date
- Status
I remember reading that stunt drivers who drive on 2 wheels ran 90-100psi. maybe ask Bo and Luke. their's didn't even blow out from creek jumps!
Originally Posted By: Pablo
Say a tire is labeled xxx pounds at 44 psi or 50 psi max - what is the absolute max I can put in the tires for MPG? I want to push the limit as hard as I can. I don't care about ride or even the best grip. What's the safety factor?
If it says 44psi, then the max is 44psi
If it says 50psi, then 50psi.
Just messin Pablo. I don't know though I'm sure Capriracer will give you a well thought answer.
BTW, one downside of high pressure is increasing stopping distance. There's something to be said for being able to stop quicker.
Say a tire is labeled xxx pounds at 44 psi or 50 psi max - what is the absolute max I can put in the tires for MPG? I want to push the limit as hard as I can. I don't care about ride or even the best grip. What's the safety factor?
If it says 44psi, then the max is 44psi
If it says 50psi, then 50psi.
Just messin Pablo. I don't know though I'm sure Capriracer will give you a well thought answer.
BTW, one downside of high pressure is increasing stopping distance. There's something to be said for being able to stop quicker.
Just want to push the limits.....maybe I'll go over by a couple PSI and report back.
44 psi will likely knock your teeth out...along with suspension components.
Don't know how the roads are in the northwest, but they are so [censored] around here, you'd risk damaging a tire on potholes with that much air pressure.
Don't know how the roads are in the northwest, but they are so [censored] around here, you'd risk damaging a tire on potholes with that much air pressure.
Originally Posted By: Pablo
Say a tire is labeled xxx pounds at 44 psi or 50 psi max - what is the absolute max I can put in the tires for MPG?
Well, the max is what's indicated on the tire sidewall. Anything higher is not considered safe by the manufacturer.
However, if you improve MPG (ever so slightly), but at the same time end up wearing out your tires unevenly and have to replace them early as well as put an additional strain on your suspension, then what are the overall savings?
Say a tire is labeled xxx pounds at 44 psi or 50 psi max - what is the absolute max I can put in the tires for MPG?
Well, the max is what's indicated on the tire sidewall. Anything higher is not considered safe by the manufacturer.
However, if you improve MPG (ever so slightly), but at the same time end up wearing out your tires unevenly and have to replace them early as well as put an additional strain on your suspension, then what are the overall savings?
Get a $65 Fluke IR gun, drive around on stock pressures and take temperatures inside-middle-outside on each tire after you get an alignment. Adjust them depending on if the edges are hot or the centre is hot. Adjust temperatures up or down for the tires when they are cool again, and keep "fine tuning" until you get it so the temperature is even across the tread.
Voila, your ideal tire pressures for wear, handling, and fuel economy.
Voila, your ideal tire pressures for wear, handling, and fuel economy.
Thanks - Great Idea!!
I wanted to know how much safety factor is built into those psi numbers....
I wanted to know how much safety factor is built into those psi numbers....
Truck tires seem to favor extremely high pressures for good mileage and good wear, lower pressures seem to be a compromise to improve the ride more than anything.
Passenger car tires overinflated center wear very badly in my experience unless they are in a heavier vehicle under heavy load, with a wider base tire. Crown Victoria cop cars are a good example of this, they typically run 44 to 51 psi in 235/50R17 tires.
Passenger car tires overinflated center wear very badly in my experience unless they are in a heavier vehicle under heavy load, with a wider base tire. Crown Victoria cop cars are a good example of this, they typically run 44 to 51 psi in 235/50R17 tires.
IIRC it is recommended to exceed the max inflation pressure if long term high speed driving is considered. This is because as the temperature of the tire increases the load carrying capacity decreases.
So you should be safe going even 10 psi above. This info comes from the Tire Rack.
http:// www .tirerack.com/tires/tiretech/techpage.jsp?techid=72
So you should be safe going even 10 psi above. This info comes from the Tire Rack.
http:// www .tirerack.com/tires/tiretech/techpage.jsp?techid=72
Never ever exceed sidewall pressure. You can exceed door post pressures.
There is a reason there is a MAX beside it. As the tires heat up, the pressure increases even moreso, so 44 pounds may become 50-55 pounds.
There is a reason there is a MAX beside it. As the tires heat up, the pressure increases even moreso, so 44 pounds may become 50-55 pounds.
I think the max on the sidewall though is a blanket statement based on the tire type, etc. If you look at tires there is no odd number such as 49psi max, or 37psi max. There seem to be different categories of tires that have different max psi per category. I would guess its something the government mandates
I've had a [censored] offbrand set of passenger 205/65/15 tires that had 35psi on the sidewall.
I've had performance tires rated at 50psi sidewall.
I've had "inbetween" tires rated at 44psi I think it was sidewall.
I would guess that these numbers are based on the category the tire is in rather than its actual rated max psi.
I've had a [censored] offbrand set of passenger 205/65/15 tires that had 35psi on the sidewall.
I've had performance tires rated at 50psi sidewall.
I've had "inbetween" tires rated at 44psi I think it was sidewall.
I would guess that these numbers are based on the category the tire is in rather than its actual rated max psi.
Kestas
Staff member
Originally Posted By: Drew99GT
... you'd risk damaging a tire on potholes with that much air pressure.
I figure it's the other way around. Tire damage from a pothole only happens when the tire completely collapses and hits the rim. More air pressure reduces the chances of this happening.
... you'd risk damaging a tire on potholes with that much air pressure.
I figure it's the other way around. Tire damage from a pothole only happens when the tire completely collapses and hits the rim. More air pressure reduces the chances of this happening.
Originally Posted By: shoz123
IIRC it is recommended to exceed the max inflation pressure if long term high speed driving is considered.
Not max inflation pressure but the vehicle's recommended inflation pressure. The link you provided clearly states:
"NOTES: Never exceed the maximum cold inflation pressure branded on the tire's sidewall."
Which is what I believe Pablo was planning on doing, judging by his initial post.
IIRC it is recommended to exceed the max inflation pressure if long term high speed driving is considered.
Not max inflation pressure but the vehicle's recommended inflation pressure. The link you provided clearly states:
"NOTES: Never exceed the maximum cold inflation pressure branded on the tire's sidewall."
Which is what I believe Pablo was planning on doing, judging by his initial post.
Originally Posted By: Kestas
Originally Posted By: Drew99GT
... you'd risk damaging a tire on potholes with that much air pressure.
I figure it's the other way around. Tire damage from a pothole only happens when the tire completely collapses and hits the rim. More air pressure reduces the chances of this happening.
Higher pressures increase the risk of impact failures according to Capri:
http://www.bobistheoilguy.com/forums/ubb...rue#Post1003279
Not sure if you were talking about the same thing though...
Originally Posted By: Drew99GT
... you'd risk damaging a tire on potholes with that much air pressure.
I figure it's the other way around. Tire damage from a pothole only happens when the tire completely collapses and hits the rim. More air pressure reduces the chances of this happening.
Higher pressures increase the risk of impact failures according to Capri:
http://www.bobistheoilguy.com/forums/ubb...rue#Post1003279
Not sure if you were talking about the same thing though...
The manual says max. 44 psi so I put 11 pounds in each tire ...
and left the spare flat.
and left the spare flat.
I put 46 in my 44 psi's.
Ride is just right. No detectable center bulging. May go with 48, but will watch for wear until I borrow the IR gun.
Ride is just right. No detectable center bulging. May go with 48, but will watch for wear until I borrow the IR gun.
- Status
