[Farzad4]

hello there i recently installed 4 sets of micheline non run flat pilot sport 4s the recomended cold tire pressure on label on side of the door says for low load 2 people maximum
225/40/19 : 2.4 bar(35psi)
255/35/19: 2.7 bar (39psi)
and for full load 4 people + stuff in trunk
225/40/19: 2.8 bar (40psi)
255/35/19: 3.3 bar (48 psi)

both seem very high to me on my other cars maximum pressure is cold 35 and these recomended looks weird what pressure should i use based on the information i gave?
and i asked a tireshop and they said the label information is not trustable put all on 32psi but i dont think he is being legit

[Farzad4]

Originally Posted by Farzad4

hello there i recently installed 4 sets of micheline non run flat pilot sport 4s the recomended cold tire pressure on label on side of the door says for low load 2 people maximum
225/40/19 : 2.4 bar(35psi)
255/35/19: 2.7 bar (39psi)
and for full load 4 people + stuff in trunk
225/40/19: 2.7 bar
255/35/19: 3.3 bar

both seem very high to me on my other cars maximum pressure is cold 35 and these recomended looks weird what pressure should i use based on the information i gave?
and i asked a tireshop and they said the label information is not trustable put all on 32psi but i dont think he is being legit

bump

[Farzad4]

i hav't being driving my car since im looking for an answer and no body seems to care

[alohasurftoad]

the PS4S has a softer sidewall than runflat so add a 2-3 psi over door placard for both front and rear. Independently adjust front and rear psi(+or-, 1-2) accordingly until you have desired ride comfort and handling(turn in sharpness) Personally, I check tpms not to exceed 39 psi at rear when warm. Front psi is usually a few less than rear.

[Farzad4]

Originally Posted by alohasurftoad

the PS4S has a softer sidewall than runflat so add a 2-3 psi over door placard for both front and rear. Independently adjust front and rear psi(+or-, 1-2) accordingly until you have desired ride comfort and handling(turn in sharpness) Personally, I check tpms not to exceed 39 psi at rear when warm. Front psi is usually a few less than rear.

i thought the door placard is for cold temperatures? my car has no TPMS it only shows the specefic tire if it got low pressure but doesnt show the exact psi , so the door says
35 front and 39 rear
then i have to set my front like 38 and 41 rear? is that for cold tires? u said watch not to go over 39 psi when warm i don't get it but even i put 38 front and 40 rear isn't that hell too much of a psi?

[alohasurftoad]

just use the door placard warm. if you want the front tighter add 1-2 psi. don't worry about it that much. just don't put 50psi. you'll be fine.

[Farzad4]

update:
i put cold temps front 2.4 bar and rear 2.7 bar and the steering feels softer and the front tires are not very accuret these pressures are higher than before so feels like the highe rit goes the less responsive it becomes

[jbiswurm]

Originally Posted by Farzad4

update:
i put cold temps front 2.4 bar and rear 2.7 bar and the steering feels softer and the front tires are not very accuret these pressures are higher than before so feels like the highe rit goes the less responsive it becomes

tire pressures are always set cold. the placard indicates cold pressures.

agree with th +3psi all around to account for non rft softer sidewall. that will help. however, a non rft will always be softer than an rft which means the soft feel will always be there to some degree.

[alohasurftoad]

thx@jbiswurm, i just checked my '15 428GC door placard. 225/255 cold tire pressures 32/35 or 220/240. so yeah, i run +3psi (35/38) on my non-runflat. the turn in feels good to me, however i've read where other members felt they lost too much turn-in response with non-runflats.

[chowser51]

I'm running +3 on my nonrunflats from the door placard. You need to drive around a bit and see if that works. I've gone to +5 before on my last set of nonrunflats. It depends on the tire's sidewall stiffness.

[luckstr]

Originally Posted by chowser51

I'm running +3 on my nonrunflats from the door placard. You need to drive around a bit and see if that works. I've gone to +5 before on my last set of nonrunflats. It depends on the tire's sidewall stiffness.

My placard (2017 440i convertible, RFT Pirelli P Zero) says 36/41 (front/rear) so if I followed your thoughts I'd inflate non RFT's to 39/44. Seems awful high too me. What am I not understanding here?

[IAmATeaf]

My PS4s tyres are XL rated so have a stiffer sidewall and I currently run my car with what’s indicated on the door sill, 37 all round.

[luckstr]

Originally Posted by alohasurftoad

the PS4S has a softer sidewall than runflat so add a 2-3 psi over door placard for both front and rear. Independently adjust front and rear psi(+or-, 1-2) accordingly until you have desired ride comfort and handling(turn in sharpness) Personally, I check tpms not to exceed 39 psi at rear when warm. Front psi is usually a few less than rear.

If I were to follow your ideas, I would have to set my rears at around 35 (cold) so that I do not exceed 39-40 (warm/hot). This is a significant difference from what is on door placard (41 cold, rear), this is on my 2017 440i convertible with Pirelli P zero RFT (OEM) 19"' P255/35

[sspade]

If it helps...

Im rolling on top of the line Continental DWS 06 (comparable to the Michelin?)...

Was recently at dealer and they set me up at 32psi cold and specifically said my pressures were too high going in. Referred me to door placard. This equates to approximately 34psi when warm and as high as 36 psi when hot. These are pressures I have personally seen on my vehicle since dealer visit.

I will continue to keep them set at a solid 32 psi cold. I think 33psi cold would also be good but beyond that... maybe too high?

[sspade]

Originally Posted by luckstr

My placard (2017 440i convertible, RFT Pirelli P Zero) says 36/41 (front/rear) so if I followed your thoughts I'd inflate non RFT's to 39/44. Seems awful high too me. What am I not understanding here?

I dont believe the +3 psi for non RFT's is an across the board, factual recommendation.

I would absolutely not run those pressures on my 440

Refer to door placard!

[sspade]

Im sorry but anyone reccomending +3 psi is doing a disservice to the board...

Unless you know better than TireRack?

"When changing to a non-run-flat tire, some drivers feel the tires may appear to be underinflated, when in fact, they are not. While you could add more pressure to correct this appearance, this often causes more rapid tread wear in the center portion of the tire. Because of this, we recommend using the same inflation pressure, even when going to non-run-flat tires."

https://blog.tirerack.com/blog/make-...run-flat-tires

[alohasurftoad]

Originally Posted by luckstr

My placard (2017 440i convertible, RFT Pirelli P Zero) says 36/41 (front/rear) so if I followed your thoughts I'd inflate non RFT's to 39/44. Seems awful high too me. What am I not understanding here?

my 428i gran coupe with 18" 441M, staggered 225/255, placard says 32front, 35rear. on my aftermarket 18" with staggered 245/255 continental extremecontact sport i use +3psi, cold 35/38, gets up to 37/40ish warm. it's wearing fine, rides fine, drives/handles fine.

on your vert', i'd probably leave it as is. i wasn't aware the placard pressures would be so different between the models, and it is a bit high already. my own personal preference is upper limit of 40ish warm.

if typical tire pressures are low-mid 30's, deviating +3psi is not that big of a deal to me.

[sspade]

Originally Posted by alohasurftoad

my 428i gran coupe with 18" 441M, staggered 225/255, placard says 32front, 35rear. on my aftermarket 18" with staggered 245/255 continental extremecontact sport i use +3psi, cold 35/38, gets up to 37/40ish warm. it's wearing fine, rides fine, drives/handles fine.

on your vert', i'd probably leave it as is. i wasn't aware the placard pressures would be so different between the models, and it is a bit high already. my own personal preference is upper limit of 40ish warm.

if typical tire pressures are low-mid 30's, deviating +3psi is not that big of a deal to me.

I am also shocked at the WIDE range of pressures that these vehicles come from factory with considering they are all fairly similar F30 brethren

[rjd_F30]

Originally Posted by Farzad4

i hav't being driving my car since im looking for an answer and no body seems to care

lol no one cares? No, it's that people tend not to reply to threads that revolve around topics that have already been discussed. If you searched before posting you would have found an abundance of answers to your question.

[luckstr]

Originally Posted by sspade

I am also shocked at the WIDE range of pressures that these vehicles come from factory with considering they are all fairly similar F30 brethren

Yes, isn't it weird that the tire pressure fluctuation is so wide? And then when one throws in the idea that door placard numbers are "designed" for the specific car so that it sounds like the car will fall apart if you do not use RFT's (or at a minimum handle terribly), one starts to reconsider going to non RFT's.

[luckstr]

Originally Posted by sspade

I am also shocked at the WIDE range of pressures that these vehicles come from factory with considering they are all fairly similar F30 brethren

Yeah, I too am confused by the wide range of recommended tire pressures across the 4 series trims ( coupe, convertible, grand coupe). As I said earlier, IF I were to increase rear pressure from 41 (door placard value) to 44 when cold, if I did any high speed traveling for an extended time, that would probably go up to 46-47 when hot and I think that is way to high.

[Randy Johnson]

Bringing this back because I just bought tires and when I was shopping I noticed this on tirerack.com. I bought Yoko ADVAN APEX V601. I'm Running 38 in the front and 40 in the rear. Will see how it feels.