Pirelli tire pressures
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Member
Joined: Mar 2024
Posts: 249
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2020 E53 AMG
Pirelli tire pressures
I drove the E53 that I ended up purchasing and was a bit disappointed with the road noise from a basically new set of Pirelli run flats. I've had summer Pirelli's in the past and was seriously unimpressed...like Toyo bricks unimpressed (and those weren't run flats). Without overdoing it, the noise through the underside of the car was certainly very un-luxury.
The car was giving me consistent pressures of about 41 psi around which seemed a bit high based on 36-38 being good in my experience. I checked them tonight and the front left was 47 psi with my seriously old school pressure gauge. Skeptical that it was more accurate than the TPMS, I set all to 36 psi. They original pressure ranged from 47 down to 41 psi.
To my surprise they all read 36 psi after driving 10km, and the noise and feel was much improved.
Question, does this make any sense at all? I simply cannot believe the TPMS was that far off. But there was a lot of extra pressure in the front left, too much to ignore.
The car was giving me consistent pressures of about 41 psi around which seemed a bit high based on 36-38 being good in my experience. I checked them tonight and the front left was 47 psi with my seriously old school pressure gauge. Skeptical that it was more accurate than the TPMS, I set all to 36 psi. They original pressure ranged from 47 down to 41 psi.
To my surprise they all read 36 psi after driving 10km, and the noise and feel was much improved.
Question, does this make any sense at all? I simply cannot believe the TPMS was that far off. But there was a lot of extra pressure in the front left, too much to ignore.
Member
Joined: Dec 2022
Posts: 186
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From: Northern California
1993 300SL,2007 RAM 2500,2009 CLK350,2011 ML550,2016 McLaren 650S,2018 AMG E63s wgn,2018 AMG SLC43
A "get off my lawn" comment. TPMS is a system that shouldn't exist but for people that don't regularly check their tire inflation.
FWIW, I blew a bundle on a Longacre Racing Products analog gauge many years ago and it's simply brilliant. One of those things that is a joy every time I use it. I'm glad I spent the money on the 4-1/2" gauge face because it's so easy to read. You can adjust pressure to 1/4 psi and know that 31.5 psi today is the same as it was last year. Swivel head and the embedded pressure release means you add a little too much air to a cold tire and release pressure to exactly what you need. (0-60 psi range is the way to go for cars)
https://www.longacreracing.com/shop....2%BD”-lb
or the 3-1/2" gauge face:
https://www.longacreracing.com/produ...21;-Tire-Gauge
Also FWIW, I've found at least on our four Mercedes that the recommended pressure on the fuel filler door is very good from a performance/ride quality perspective. I have gone up 1 psi, and with this gauge, you can actually run experiments with slightly different pressures to decide the optimal pressure for your driving style.
FWIW, I blew a bundle on a Longacre Racing Products analog gauge many years ago and it's simply brilliant. One of those things that is a joy every time I use it. I'm glad I spent the money on the 4-1/2" gauge face because it's so easy to read. You can adjust pressure to 1/4 psi and know that 31.5 psi today is the same as it was last year. Swivel head and the embedded pressure release means you add a little too much air to a cold tire and release pressure to exactly what you need. (0-60 psi range is the way to go for cars)
https://www.longacreracing.com/shop....2%BD”-lb
or the 3-1/2" gauge face:
https://www.longacreracing.com/produ...21;-Tire-Gauge
Also FWIW, I've found at least on our four Mercedes that the recommended pressure on the fuel filler door is very good from a performance/ride quality perspective. I have gone up 1 psi, and with this gauge, you can actually run experiments with slightly different pressures to decide the optimal pressure for your driving style.
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Joined: Sep 2018
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From: New Orleans Area
2015 E400 Sedan
the longacre is a good product and great accuracy of +/-0.25PSI for the entire scale.
most analog pressure gages are accurate to 1% of full scale and then if bourdon tube type really only accurate in middle of scale I.E. need vertical on gage.
I do not think TPMS is accurate based onmyexperience of comparing to some decent pressure gages I have.
Always seems to read 4PSI high.
I sue this now gage now: has the fill and release and digital with ice big back lit numbers to read.
Accuracy is +/- 1.2psi which is good enough for my road going car
I love the valve stem chuck - so easy to attach and remove without much air loss.
Astro has analog versions too which are more accurate but not much +/- <1psi
Astro makes them for MATCO tools.
most analog pressure gages are accurate to 1% of full scale and then if bourdon tube type really only accurate in middle of scale I.E. need vertical on gage.
I do not think TPMS is accurate based onmyexperience of comparing to some decent pressure gages I have.
Always seems to read 4PSI high.
I sue this now gage now: has the fill and release and digital with ice big back lit numbers to read.
Accuracy is +/- 1.2psi which is good enough for my road going car
I love the valve stem chuck - so easy to attach and remove without much air loss.
Astro has analog versions too which are more accurate but not much +/- <1psi
Astro makes them for MATCO tools.
