Opinions on tire wear please....
#16
Three Wheelin'
Just bare in mind all the Porsche's recommended adjustments are a compromise. This includes tire pressure, alignment specs and all possible parameters. The fact that you lowered your car and perhaps drive a bit conservatively when it comes to cornering, the weight, load and how you take a line all have direct impact on the tire wear. I would start by decreasing tire pressure, because Porsche 911 rear tires are very wide and any more air pressure tend to load the outside more so than the average sedan.
#17
Just a car guy
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Just bare in mind all the Porsche's recommended adjustments are a compromise. This includes tire pressure, alignment specs and all possible parameters. The fact that you lowered your car and perhaps drive a bit conservatively when it comes to cornering, the weight, load and how you take a line all have direct impact on the tire wear. I would start by decreasing tire pressure, because Porsche 911 rear tires are very wide and any more air pressure tend to load the outside more so than the average sedan.
#18
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Thread Starter
20,000 miles! Damn, I'd be thrilled if mine had that kind of mileage. I have yet to get more than 8000 miles out of any rear tire...and I drive like Miss Daisy.
#19
Burning Brakes
I've got 5k miles on my pilot sports. Perfect wear pattern and tons of life left. I would bet the average person thinks they are new
#20
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Thread Starter
Just bare in mind all the Porsche's recommended adjustments are a compromise. This includes tire pressure, alignment specs and all possible parameters. The fact that you lowered your car and perhaps drive a bit conservatively when it comes to cornering, the weight, load and how you take a line all have direct impact on the tire wear. I would start by decreasing tire pressure, because Porsche 911 rear tires are very wide and any more air pressure tend to load the outside more so than the average sedan.
#21
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Thread Starter
It's comments like this that make me feel like something isn't right. There was a new set of BS S04s on car when I got it. Inside edge to cords in 5000 miles. Replaced with Falken FK453s and had it realigned. That set of rears lasted about 7500 miles. Another set of Falkens, alignment and about 8000kms. Michelin PSS, alignment and this wear and mileage (6800 miles). First sets I stick with factory recommended tire pressures (44psi rear), Michelins I dropped to 40 psi. No drag racing, no significant high speed runs, three track days each year. Majority is city, back road and highway.
#22
Burning Brakes
It's comments like this that make me feel like something isn't right. There was a new set of BS S04s on car when I got it. Inside edge to cords in 5000 miles. Replaced with Falken FK453s and had it realigned. That set of rears lasted about 7500 miles. Another set of Falkens, alignment and about 8000kms. Michelin PSS, alignment and this wear and mileage (6800 miles). First sets I stick with factory recommended tire pressures (44psi rear), Michelins I dropped to 40 psi. No drag racing, no significant high speed runs, three track days each year. Majority is city, back road and highway.
I can only assume that your issue is due to lowering it and the camber not being able to be put in spec.
#23
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Thread Starter
#24
Rennlist Member
Here is my right rear, the left rear looked just like it and my two fronts were not worn at all. These were Continental DWS all season tires. They were on the car for about 18,000 street miles, I run about 34 PSI or so. When you looked at the rears without getting under the car, they looked great....but go under the car and you'll see the inboard shoulder is completely worn compared to the outboard shoulder. I put some Michelin Pilot Sport 4S's on them. They are sticky! But the car is in hibernation.
#25
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Thread Starter
Here is my right rear, the left rear looked just like it and my two fronts were not worn at all. These were Continental DWS all season tires. They were on the car for about 18,000 street miles, I run about 34 PSI or so. When you looked at the rears without getting under the car, they looked great....but go under the car and you'll see the inboard shoulder is completely worn compared to the outboard shoulder. I put some Michelin Pilot Sport 4S's on them. They are sticky! But the car is in hibernation.
#26
Rennlist Member
I was just thinking about tire pressure yesterday.
What's the lowest one can safely go?
I know the front is light and could use less than the tire manufacturer suggest.
Commuter car with nice twisty roads to and from work, down hill in the morning and uphill home makes for a great end of the day.
What's the lowest one can safely go?
I know the front is light and could use less than the tire manufacturer suggest.
Commuter car with nice twisty roads to and from work, down hill in the morning and uphill home makes for a great end of the day.
#27
#28
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I was just thinking about tire pressure yesterday.
What's the lowest one can safely go?
I know the front is light and could use less than the tire manufacturer suggest.
Commuter car with nice twisty roads to and from work, down hill in the morning and uphill home makes for a great end of the day.
What's the lowest one can safely go?
I know the front is light and could use less than the tire manufacturer suggest.
Commuter car with nice twisty roads to and from work, down hill in the morning and uphill home makes for a great end of the day.
Use an IR temperature gun (or better yet, a tire pyrometer). At the end of a spirited drive (push hard - as much as traffic and road conditions allow) - check the inboard, center and outboard tire surface temperatures. Do this as quickly as possible after stopping. Log the data over several trips and look for trends. Hopefully your drive will have an equal number of rights and lefts. If not, try to look for a mid-point stop that is close to the balance of direction and severity. You can also focus on just one side at a time - take what is learned and apply to the other side.
Once a decent set of data are captured, analyze for ways to equalize the readings. I.e. if the center is warmer than the sides, you can drop pressure. Any changes should be in small increments (unless temp deltas are large). If one side or the other is hotter, than camber change should be considered. It's unlikely you would ever get temps uniform, even after much testing and refining. Just getting things closer will be a good step.
Surface temps will drop quickly. Be sure to note the order in which each tire was checked. Mix this up so enough data is collected with the LF checked first, etc. Then move to a different corner as first up, for additional data-sets. It will probably take a lot of trials - but the more data you have to work with, the more likely a good picture will emerge. Some data sets will be ruined for any number of reasons (rain, cold, speed, etc). Keep the data - but be sure to note what happened and why it should not be used for any calculations. Consistency in testing is key.
#29
Rennlist Member
Factory spec (44psi) assumes max load, 3-4 passengers, stock tire size does well at about 36psi if normally driven alone.