Max Tire Inflation

[dkryan]

I am looking to replace the OEM Conti ProContacts on my 2014 Altima 2.5 SL with either the Michelin Premier A/S or the Pirelli P7 A/S Plus.

In reviewing the specs on the P7 A/S Plus on the Tire Rack website, I noted the max inflation pressure for the "V" rated tire as 51 psi.

I have yet to own a set of "H" or "V" skins that had a max inflation pressure above 44 psi. Interestingly enough, the same
tire in an "H" rating lists a max Inflation pressure of 44 psi.

I run 35/32 psi in the fwd Altima. The weight of the engine over the tires somewhat dictates a higher psi than in the rear tires with minimal weight in the tail end.

Could I run 39/35 psi on those P7s (alignment and balance being in spec) based on the higher max sidewall pressure and still not cause pre-mature wear?

 

[The_Jeff]

I think you'd rattle your strut mounts to death at 40 psi.

 

[dkryan]

Originally Posted By: eljefino
I think you'd rattle your strut mounts to death at 40 psi.


Okay. Quite possibly.

But, maybe I was looking for feedback, as well, as to why the max inflation pressure has gone up to 51 psi?

I noticed 50 psi+ on a few Pirelli performance tires.

 

[dkryan]

And by the way, the door jamb Nissan recommended pressure of 30 psi front and rear ain't gonna get it.

I don't want that 1970s Lincoln Town Car "boulevard ride."

I have managed 48k miles on the 40k mile Conti ProContacts based on 7k mile rotations and 11k mile alignments.

I can't imagine what the tires would look like sitting in the garage at 30 psi and a max inflation pressure of 51 psi.

 

[SatinSilver]

Anyways, tire psi aside I'd get the P7 Plus.

 

[53' Stude]

LOL!

 

[bioburner]

Having just looked at the Conti tires as replacement on my Transit they are supposed to be 80k tires. Pretty spendy too at $120.

 

[dkryan]

Originally Posted By: SatinSilver
Anyways, tire psi aside I'd get the P7 Plus.


Yep. Probably will go that way..

 

[dkryan]

Originally Posted By: bioburner
Having just looked at the Conti tires as replacement on my Transit they are supposed to be 80k tires. Pretty spendy too at $120.


Conti ProContacts are a $200 tire locally. And not cheap on TireRack, either. And a 500 treadwear rating.

Where do you get 80k and $120?

 

[SatinSilver]

I'd also get them during the Black Friday sale on DTD or Discount Tire. Prob get a $100 rebate on those from DT.

edit: I'd also make sure the tire has an A rating for temperature. The General RT43 has a B rating and the psi varies quite a bit according to the onboard computer reading. Where the oem Michelins didn't fluctuate nearly as much.

 

[AZjeff]

Originally Posted By: dkryan
I can't imagine what the tires would look like sitting in the garage at 30 psi and a max inflation pressure of 51 psi.


What's the correlation between max pressure and anything? You want to go to 39 psi because the max has gone up. It's going to ride stiffer than where you're at now regardless of max. What do you think you're gaining?

 

[fdcg27]

I know that as we approach 40 psi on our newer Accord the ride quality becomes unacceptably harsh.
Don't recall the door jamb recommendations, but they're pretty low.
We therefore compromise at around 35 psi all around.
I don't think you're going to want to run much more than what you're using now in your car regardless of what the sidewall recommended maximum pressure of these Pirellis might be.
Incidentally, I have a set of these on deck for our newer Accord which is at 58K on its OEM Dunlops. A couple of other members have put these Pirellis on their '12 Accords and have reported good results.
I'll mount these tires in the next two weeks or so, before snow becomes a serious threat.
You'll probably like these on your Altima as well.

 

[mclasser]

I assume Ohio roads take a beating in the winter so riding with over-inflated tires won't make for a comfortable commute.

 

[SumpChump]

Originally Posted By: dkryan
Originally Posted By: SatinSilver
Anyways, tire psi aside I'd get the P7 Plus.


Yep. Probably will go that way..


I have the p7 Plus on my 2013 Camry 2.5L. They have been great performers.

 

[CapriRacer]

Originally Posted By: dkryan
I am looking to replace the OEM Conti ProContacts on my 2014 Altima 2.5 SL with either the Michelin Premier A/S or the Pirelli P7 A/S Plus.

In reviewing the specs on the P7 A/S Plus on the Tire Rack website, I noted the max inflation pressure for the "V" rated tire as 51 psi.

I have yet to own a set of "H" or "V" skins that had a max inflation pressure above 44 psi. Interestingly enough, the same
tire in an "H" rating lists a max Inflation pressure of 44 psi.

I run 35/32 psi in the fwd Altima. The weight of the engine over the tires somewhat dictates a higher psi than in the rear tires with minimal weight in the tail end.

Could I run 39/35 psi on those P7s (alignment and balance being in spec) based on the higher max sidewall pressure and still not cause pre-mature wear?




dkryan,

First read my webpage on the subject of load tables: Barry's Tire Tech: Load Tables Be sure to read about the Notes on page 1-34!

Short version: The maximum pressure listed on the sidewall is pretty arbitrary - except to say that S and T speed rated tires have to have at least 35 psi, H rated tires have to have 44 psi max, and V and higher need 51 psi max - because that is the test pressure for the speed rating test. But the load carrying capacity of a tire is independent of the speed rating.

So you shouldn't be paying attention to what the max pressure is on the tires. Pay attention to what the vehicle manufacturer says on the vehicle tire placard.

 

[Rolla07]

I had the P7's and ran them at 30 -32 psi all around with no issues. I did run them at 35psi but you lose traction when too much air pressure. Tire max is irrelevant as door jam represents best mix of comfort, traction and tire wear. So you want your tires to last long and dont care about safety? Thats up to you and depends on your experience but I run max 1-2 psi over door jam and its perfect. Besides sacrificing traction, not sure what your goal is. I put priority in traction and safety before making my tires last longer.

 

[Rolla07]

Originally Posted By: CapriRacer
Originally Posted By: dkryan
I am looking to replace the OEM Conti ProContacts on my 2014 Altima 2.5 SL with either the Michelin Premier A/S or the Pirelli P7 A/S Plus.

In reviewing the specs on the P7 A/S Plus on the Tire Rack website, I noted the max inflation pressure for the "V" rated tire as 51 psi.

I have yet to own a set of "H" or "V" skins that had a max inflation pressure above 44 psi. Interestingly enough, the same
tire in an "H" rating lists a max Inflation pressure of 44 psi.

I run 35/32 psi in the fwd Altima. The weight of the engine over the tires somewhat dictates a higher psi than in the rear tires with minimal weight in the tail end.

Could I run 39/35 psi on those P7s (alignment and balance being in spec) based on the higher max sidewall pressure and still not cause pre-mature wear?




dkryan,

First read my webpage on the subject of load tables: Barry's Tire Tech: Load Tables Be sure to read about the Notes on page 1-34!

Short version: The maximum pressure listed on the sidewall is pretty arbitrary - except to say that S and T speed rated tires have to have at least 35 psi, H rated tires have to have 44 psi max, and V and higher need 51 psi max - because that is the test pressure for the speed rating test. But the load carrying capacity of a tire is independent of the speed rating.

So you shouldn't be paying attention to what the max pressure is on the tires. Pay attention to what the vehicle manufacturer says on the vehicle tire placard.


Was looking to see if you replied to this thread.

Thumbs up!

 

[circuitsmith]

Originally Posted By: dkryan
I have yet to own a set of "H" or "V" skins that had a max inflation pressure above 44 psi.


Currently running H rated Conti Pure Contact and previous Yokohama Avid Envigor both rated 51 psi.

 

[AZjeff]

Listen to CapriRacer. A while ago I asked him for some advice with some slightly oversize tires on one of my vehicles. He recommended a pressure that was based on tire specs, vehicle weight, etc. Mileage has been equal to stock size, ride is great, wearing fine. Sometimes we're given very good advice if we're smart enough to consider it.

 

[circuitsmith]

Originally Posted By: dkryan
And by the way, the door jamb Nissan recommended pressure of 30 psi front and rear ain't gonna get it.

I don't want that 1970s Lincoln Town Car "boulevard ride."

I have managed 48k miles on the 40k mile Conti ProContacts based on 7k mile rotations and 11k mile alignments.

I can't imagine what the tires would look like sitting in the garage at 30 psi and a max inflation pressure of 51 psi.


So you know more than the car maker, eh?
Have you ever actually tried using the "proper" air pressure?
I'll admit most of the time I have no rear seat passengers and less than 25lb in the "trunk" of my Matrix, so I run 28 psi in the rears instead of 32 psi as the door sticker calls for.
It's a little quieter and less harsh going over bumps; not at all a "boulevard ride".
Close inspection shows the front tires still have a larger contact patch than rear.
If I'm going to carry a load then I bring the rears up to 32.