Optimal Daily PSI?
#1
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2010 C300 4MATIC........ 2011 C63 AMG.............. 2015 CLS400 4MATIC.....
Optimal Daily PSI?
Hey guys,
Just wanted to hear some opinions on what psi is best to run for daily driving use.
235/35/19 F
265/30/19 R
Conti DWS06
Currently running about 40 front and 45 rear (according to a note on tirerack, 42+psi is required for load rating for rears?)
Just wanted to hear some opinions on what psi is best to run for daily driving use.
235/35/19 F
265/30/19 R
Conti DWS06
Currently running about 40 front and 45 rear (according to a note on tirerack, 42+psi is required for load rating for rears?)
#3
Open the fuel door, inside there's a placard with suggested tire pressures depending on load.
40 all around for me too... What I'm interested in, is what tire pressures some of you use on the track
40 all around for me too... What I'm interested in, is what tire pressures some of you use on the track
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2010 C300 4MATIC........ 2011 C63 AMG.............. 2015 CLS400 4MATIC.....
Good to hear some track pressures too.
Running different size rims and tires than oem so I would think it would not be the same, 30 front 35 rear is what I kept my oem ones at.
Running different size rims and tires than oem so I would think it would not be the same, 30 front 35 rear is what I kept my oem ones at.
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2014 C63 Coupe
If you really want to determine the correct pressure to support the same loads as manufacturer specs for size, load rating and inflation, you can peruse the attached document.
Note: this is geared towards trucks but the concepts are the same and can be applied to passenger car tires as well.
Essentially though, you need to duplicate the manufacturer's load rating per tire or axle by determining what pressure you need in your new tires to meet or exceed the same. That information should be relatively easy to obtain from the new tire manufacturer.
Or you can just guess and say well the internet says this so I'm sure it's fine.
Note: this is geared towards trucks but the concepts are the same and can be applied to passenger car tires as well.
Essentially though, you need to duplicate the manufacturer's load rating per tire or axle by determining what pressure you need in your new tires to meet or exceed the same. That information should be relatively easy to obtain from the new tire manufacturer.
Or you can just guess and say well the internet says this so I'm sure it's fine.
Last edited by Ludedude; 09-12-2017 at 05:40 PM.
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BLKROKT (09-14-2017)
#7
Many of us also factor in handling, even tread wear and relative ride comfort into the equation. That said, IMO 40lbs all-around is an excellent starting point. I'm at 40F/39R myself on 245/275 (19).
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#8
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I just finished a set of DWS, the set that was on the car when I bought it.
the rears wear like there's too much pressure, if you commute alone in the car, even at 41 PSI.
I was trying to run 39, but then a low pressure warning kicks in and it is a slight nuisance to erase the message.
I am starting to look at the rear Michelin PSS and I start to see signs of biased center wear at 41 PSI. I have to reset the sensors somehow for a lower pressure.
the rears wear like there's too much pressure, if you commute alone in the car, even at 41 PSI.
I was trying to run 39, but then a low pressure warning kicks in and it is a slight nuisance to erase the message.
I am starting to look at the rear Michelin PSS and I start to see signs of biased center wear at 41 PSI. I have to reset the sensors somehow for a lower pressure.
#10
MBWorld Fanatic!
I just finished a set of DWS, the set that was on the car when I bought it.
the rears wear like there's too much pressure, if you commute alone in the car, even at 41 PSI.
I was trying to run 39, but then a low pressure warning kicks in and it is a slight nuisance to erase the message.
I am starting to look at the rear Michelin PSS and I start to see signs of biased center wear at 41 PSI. I have to reset the sensors somehow for a lower pressure.
the rears wear like there's too much pressure, if you commute alone in the car, even at 41 PSI.
I was trying to run 39, but then a low pressure warning kicks in and it is a slight nuisance to erase the message.
I am starting to look at the rear Michelin PSS and I start to see signs of biased center wear at 41 PSI. I have to reset the sensors somehow for a lower pressure.
#11
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2014 C63 Coupe
Yeah, it's under the tire pressure menu in the speedo screen. Under service I think? If you select the tire pressure display then click OK on the steering wheel, it will ask if you want to reset the sensors to the current pressures as a default.
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Crap. Now I am at work. I forgot to check on the way in I will do it on the way out.
#13
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The tire screen is the second last one, I think.
From the AMG screen, go left by one or two. You should see tire pressure. If you go into tire pressure, it'll show you all 4 of your tires' PSI. If you press the down button (not the OK button), it will ask if you want to confirm these as the new reference values. I just did this a few weeks ago and got stuck with setting the new reference values. I kept pressing Ok and other combinations, even tried pressing the phone call button. It's the down arrow!
Currently running 42 front 32 rear for street on 245/265 19" MPSS.
From the AMG screen, go left by one or two. You should see tire pressure. If you go into tire pressure, it'll show you all 4 of your tires' PSI. If you press the down button (not the OK button), it will ask if you want to confirm these as the new reference values. I just did this a few weeks ago and got stuck with setting the new reference values. I kept pressing Ok and other combinations, even tried pressing the phone call button. It's the down arrow!
Currently running 42 front 32 rear for street on 245/265 19" MPSS.
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Ludedude (09-14-2017)
#14
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These are my cold temps. 39 f and 41 r
#15
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The tire screen is the second last one, I think.
From the AMG screen, go left by one or two. You should see tire pressure. If you go into tire pressure, it'll show you all 4 of your tires' PSI. If you press the down button (not the OK button), it will ask if you want to confirm these as the new reference values. I just did this a few weeks ago and got stuck with setting the new reference values. I kept pressing Ok and other combinations, even tried pressing the phone call button. It's the down arrow!
Currently running 42 front 32 rear for street on 245/265 19" MPSS.
From the AMG screen, go left by one or two. You should see tire pressure. If you go into tire pressure, it'll show you all 4 of your tires' PSI. If you press the down button (not the OK button), it will ask if you want to confirm these as the new reference values. I just did this a few weeks ago and got stuck with setting the new reference values. I kept pressing Ok and other combinations, even tried pressing the phone call button. It's the down arrow!
Currently running 42 front 32 rear for street on 245/265 19" MPSS.
#16
Member
The tire screen is the second last one, I think.
From the AMG screen, go left by one or two. You should see tire pressure. If you go into tire pressure, it'll show you all 4 of your tires' PSI. If you press the down button (not the OK button), it will ask if you want to confirm these as the new reference values. I just did this a few weeks ago and got stuck with setting the new reference values. I kept pressing Ok and other combinations, even tried pressing the phone call button. It's the down arrow!
Currently running 42 front 32 rear for street on 245/265 19" MPSS.
From the AMG screen, go left by one or two. You should see tire pressure. If you go into tire pressure, it'll show you all 4 of your tires' PSI. If you press the down button (not the OK button), it will ask if you want to confirm these as the new reference values. I just did this a few weeks ago and got stuck with setting the new reference values. I kept pressing Ok and other combinations, even tried pressing the phone call button. It's the down arrow!
Currently running 42 front 32 rear for street on 245/265 19" MPSS.
Also, the pressures listed in my fuel door are different from listed in the driver's door.
#18
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#20
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I'm running this for traction reasons. Is 30 PSI really too low for daily? People here run that or even lower at the strip or track.
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W204 C63 Coupe, W166 ML350 BlueTEC, 928GT, C5 Z06 & IS300 race cars, EQE 4Matic+ on order
Second, the high tire temperatures on the track will cause the cold tire pressures to rise by about 10 psi. The most I've seen on the street is about 4 psi.
Third, at the track the load in the car is usually that of just the driver. On the street you may also have to carry a passenger or three as well as some cargo.
Fourth, tire longevity on a race track is measured in hours as opposed to years, so tire wear is not a concern. And, contrary to what some people may tell you, the rims absolutely DO suffer and are also wear and tear items. Aluminum alloys definitely weaken from fatigue and I wouldn't even think of using 10 year old rims on my track rat when entering a corner at 240 km/h and 1.8 lateral Gs, just like I wouldn't use an expired seat or safety harness.
So - when you take all of these factors into account, the cold pressures that you start with at the track need to be about 12-15 psi lower than what you need on the road.
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Duffer4126 (07-21-2018)