not liking Michelin Pilot Sport 4S - what's going on?
01-22-2019, 02:20 PM
#32
Three Wheelin'
I'll try seeing how low I can drop the PSI. I messed around plenty with P Zero's and they were sloppy and slow to respond with lower pressure which is what I find typical with tires. Dropping PSI was my first test and PS4S and had similar result, but with colder and variable temps, I quickly set it back to sticker. For example its going from 55F down to 15F tonight here.
Manual says for 4S...
Standard
31/39 partly load
34/44 fully load
Comfort
29/33 partly load
31/39 fully load
I assume full load car holding weight? Meaning the more weight on the car the higher the PSI should be? Looks like heavier cars (PDK, AWD) call for more PSI.
Also it mentions that the PSI is set at 68F/20C meaning if you set it at 40F or lower to sticker PSI, that's even worse? According to the logic tire pressure would be really low in cold temps if you went with comfort (26 or lower front, which I know will be really sloppy).
I'm confused because my sticker says 35/45, but that's not even in the manual. If anything its 34/44 max. Nonetheless, according to the manual it does seem mine is set too high. Maybe this works better for P Zeros and PS4S works best with lower PSI.
http://www.porscheownersmanuals.com/...Technical-data
Manual says for 4S...
Standard
31/39 partly load
34/44 fully load
Comfort
29/33 partly load
31/39 fully load
I assume full load car holding weight? Meaning the more weight on the car the higher the PSI should be? Looks like heavier cars (PDK, AWD) call for more PSI.
Also it mentions that the PSI is set at 68F/20C meaning if you set it at 40F or lower to sticker PSI, that's even worse? According to the logic tire pressure would be really low in cold temps if you went with comfort (26 or lower front, which I know will be really sloppy).
I'm confused because my sticker says 35/45, but that's not even in the manual. If anything its 34/44 max. Nonetheless, according to the manual it does seem mine is set too high. Maybe this works better for P Zeros and PS4S works best with lower PSI.
http://www.porscheownersmanuals.com/...Technical-data
01-22-2019, 02:36 PM
#33
Burning Brakes
01-22-2019, 02:38 PM
#34
Rennlist Member
dumb question, what's partly loaded and fully loaded? Meaning passengers in car? If you have fully loaded wouldn't you want higher PSI to compensate the weight?
01-22-2019, 03:27 PM
#35
Three Wheelin'
Correct.
01-22-2019, 03:29 PM
#36
01-22-2019, 05:56 PM
#37
Race Car
01-22-2019, 07:01 PM
#38
This has helped, count me as another victim of new Pilot 4S install with door sticker pressures from the get go. I let out 6 from the front and 10 from the rears (was 39/48), much better now. Could probably go more.
01-22-2019, 10:30 PM
#40
Rennlist Member
01-22-2019, 11:47 PM
#41
Rennlist Member
Okay this is weird. I ran P-zeros summer 2017 and Michelin PS4's summer 2018. I ran 30/33 both years so, yeah, you should probably drop the pressure...
BUT
I also experienced that "wandering" you describe! It seemed like it wanted to drift ever so slightly to the left or to the right depending on the gradient of the road. I thought it was alignment. When I put my winter wheels/tires back on the car last autumn, I had the alignment adjusted and the wandering went away. Maybe it was the tires?
BUT
I also experienced that "wandering" you describe! It seemed like it wanted to drift ever so slightly to the left or to the right depending on the gradient of the road. I thought it was alignment. When I put my winter wheels/tires back on the car last autumn, I had the alignment adjusted and the wandering went away. Maybe it was the tires?
01-23-2019, 12:57 AM
#42
Rennlist Member
Originally Posted by 911boy
Its going to handle WAAAY better with lower pressures.
01-23-2019, 01:31 AM
#43
Rennlist Member
echo much of the input provided above
my own data points for your reference for mich psss or ps4 on modern 911 chassis
normal street driving (cold)
32 front
36 rear
will run up to 35-36 front and 39-40 rear when hot
track driving
27 f 29 r cold
will run up to 35 f 36/37 r when hot
store at 48-50 psi (car not driven for more than 3-4 wks)
mpss has a slightly firmer sidewall than mp4s but grip on mp4s is better under punishing conditions
also reiterate that these are summer compound tires they will NOT work as designed in close to freezing temps
my own data points for your reference for mich psss or ps4 on modern 911 chassis
normal street driving (cold)
32 front
36 rear
will run up to 35-36 front and 39-40 rear when hot
track driving
27 f 29 r cold
will run up to 35 f 36/37 r when hot
store at 48-50 psi (car not driven for more than 3-4 wks)
mpss has a slightly firmer sidewall than mp4s but grip on mp4s is better under punishing conditions
also reiterate that these are summer compound tires they will NOT work as designed in close to freezing temps
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4flynlow (12-24-2019)
01-23-2019, 08:36 AM
#45
what are you running your GTS’s pressures at? I’ve never been happy with the P0s on my GTS. Thanks