How much extra would you pay for acoustic tech tire?

[dsgerbc]

Hello all.
Shopping for tires to downsize from OEM 20"
There's the Michelin P4S in 255/40/19 @ $281.99/tire on tirerack
And there's Michelin P4 in Volvo spec, same size, @ $354.89/tire.

Is it worth it? I can only find limited reviews on acoustic tires, and some user reviews here that commented on noise level when switching to winter tires. Anyone went from stock P4S to non-acoustic P4S?

 

[artsci]

Nothing. They make no noticeable difference at all. This is just a gimmick to charge more for tires that have a six inch wide strip of foam in them that probably costs the tire manufacturer about $2.50. Acoustic tests show that the difference is barely audible.

 

[dfwatt]

Hello all.
Shopping for tires to downsize from OEM 20"
There's the Michelin P4S in 255/40/19 @ $281.99/tire on tirerack
And there's Michelin P4 in Volvo spec, same size, @ $354.89/tire.

Is it worth it? I can only find limited reviews on acoustic tires, and some user reviews here that commented on noise level when switching to winter tires. Anyone went from stock P4S to non-acoustic P4S?

While you can debate about whether or not 1 DB is significant - which is what is typically measured for the quieting effect of acoustic foam - that's not the only difference between the generic Pilot Sport 4S and the version of that tire for Tesla vehicles. There are structural differences that we don't really understand very well, but the clearest index of that is that the tread on the 235 / 35 and also on the 275 / 30 Tesla specific 4S which I run on my car is usefully wider then tires nominally of the same size. Additionally there are again speculative reports that the center section of the tire uses a harder compound to obviate the asymmetry of accelerated crown wear from higher tire pressures. Michelin is very tight-lipped about what they've done to that tire and Tesla is similarly non-transparent. One speculation is that they went to a softer and wider outer tread compound in order to get more cornering grip without the extra rolling resistance involved in Tire upsizing. If you look at the Tire Rack website for the Michelin Pilot Sport 4S you will see that the Tesla specific Tire in the 235 / 35 - 20 size is actually as wide in terms of its tread but not its section width compared to an average of the three available 255 / 35 tires. While this is a speculation it squares with the fact that the tire handles tracking more poorly than its antecedent and closest relative the Michelin Super Sport. That tire was not nearly as vulnerable to chunking as the 4S on Teslas. So at the very least it looks like the tire Compound on the outer portion of the tire which does a lot of the work in heavy cornering is softer at least then the tire Compound on the Super Sport.

As for one poster's claim that the acoustic foam makes no difference, there are a lot of people who will disagree with him on that who are disappointed to find that the generic 4S is discernibly louder. Although 1db is not a lot when you add that other things that you can do to quiet the car including the wind noise reduction kit from RPM, additional weather seals on the doors, dynamating, and the cloth interior roof / sun shades, we've knocked easily 5db off the car's Highway noise profile. That's really significant.

One question might be why do you want to downsize the tire? Is it because you're concerned about vulnerability to pothole and impact damage? The problem with the tire that you asked about the 255 / 40 - 19 is that it's a half an inch taller. This means it will not clear the front suspension member without really changing the offset as that front suspension member curls laterally and leaves precious little room even with tires with stock rolling diameter. Are you trying to change the rolling diameter deliberately or did you simply select the 255 because you wanted more tread width? If it's the latter think about the 265/35 - 19. That looks like the sweet spot for people who are tracking the car and looking for maximum tread width

 

[SomeJoe7777]

Hello all.
Shopping for tires to downsize from OEM 20"
There's the Michelin P4S in 255/40/19 @ $281.99/tire on tirerack
And there's Michelin P4 in Volvo spec, same size, @ $354.89/tire.

Is it worth it? I can only find limited reviews on acoustic tires, and some user reviews here that commented on noise level when switching to winter tires. Anyone went from stock P4S to non-acoustic P4S?

I have a bit different take than artsci. I have seen some objective audio measurements of the foam-equipped tires vs non-foam-equipped, and on the sound meter, there is a measurable difference in noise. (See here.) However, that has some caveats:

1. The difference in absolute noise is pretty small. A few dB at most.
2. The frequency range where the noise is reduced are the mid frequencies (echo within the tire, sharper road imperfections). Lower frequencies (concrete rumble, larger bumps) are not really affected.
3. While noticable on the meter, whether it's noticable to your ears is very debatable. Many of the human testers say they could not tell the difference with their ears.

Some additional things to know about acoustic-foam-equipped tires:

1. They are more expensive than the non-foam counterpart. Given the small benefit to noise reduction, the value of that cost increase is debatable.
2. Emergency flat repair products that can seal a tire from the inside do not work on foam-equipped tires since the sealant cannot reach the puncture underneath the foam.
3. Many tire shops will not attempt to repair a foam-equipped tire with a standard inside-the-tire patch, as they do not want to accept liability for removing a portion of the foam. They will make you buy a new tire.
4. If noise reduction is the goal, start by using a different size and construction tire. As an example, moving from a Max Performance Summer tire in 235/35R20 (such as the Michelin Pilot Sport 4S) to a Grand Touring tire in 235/45R18 (such as the Michelin Primacy MXM4) will inherently reduce noise. The amount of noise reduction by this change will likely exceed what foam can deliver.
5. To maintain quiet tires, they need to be rotated throughout their life (whether foam-equipped or not). Some modern advise suggests that rotation is no longer necessary, but if you don't, all tires will get noisy on the back half of their life.

 

[dsgerbc]

While you can debate about whether or not 1 DB is significant - which is what is typically measured for the quieting effect of acoustic foam -

1DB is not insignificant, since it's a log10 scale. It's what, 25% higher power of noise wave?

As for one poster's claim that the acoustic foam makes no difference, there are a lot of people who will disagree with him on that who are disappointed to find that the generic 4S is discernibly louder.

Do you have links to those claims? I'm having trouble finding those.

 

[dsgerbc]

I have a bit different take than artsci. I have seen some objective audio measurements of the foam-equipped tires vs non-foam-equipped, and on the sound meter, there is a measurable difference in noise. (See here.)

Yes, that's the only journal test I could find. But it's also not on Michelins.

1. They are more expensive than the non-foam counterpart. Given the small benefit to noise reduction, the value of that cost increase is debatable.

Which is exactly why I posted this. I'd like to hear what people think, especially from those that went with generic P4S.

3. Many tire shops will not attempt to repair a foam-equipped tire with a standard inside-the-tire patch, as they do not want to accept liability for removing a portion of the foam. They will make you buy a new tire.

What's wrong with removing a bit of foam? But this sounds like a reason to buy from a place with decent roadhazard coverage.

4. If noise reduction is the goal,

It's not. I'm evaluating if it's worth paying for it in the P4S-level performance tire.

 

[dfwatt]

1DB is not insignificant, since it's a log10 scale. It's what, 25% higher power of noise wave?


Do you have links to those claims? I'm having trouble finding those.

A 1db interval is generally thought of as the minimum for a just perceptible loudness augmentation, and as another poster has already pointed out we do have differential auditory sensitivity. Interestingly enough our highest sensitivity is to the vocal range of the female voice fundamentals. And some of Tire whine falls into that treble area. I believe Tire Rack has tested this and if you go to Tire racks website I think there is a link with some results comparing tires with and without acoustic foam. Don't have time to dig that out myself right now but I'm pretty sure that's where I saw it. But also like the other poster pointed out it's all trade-offs. The tires are heavier and harder to repair. And unfortunately that little bit of extra mass is located far out in the spinning assembly, contributing significantly to rotational inertia therefore. If you want a lighter Tire, and you're looking for that 10th or fraction of 1/10 quicker 0 to 60 and quarter mile times , don't put an acoustic foam Tire on your model 3

 

[JamesBrown]

Most studies show that the minimum change in the sound level of individual events that an average human ear can detect is about 3 dB.
How Much is a Decibel? Sound Perception Vs. Reality | ABD Engineering & Design

A 1dB change is not worth a $300 increase in price and higher repair/replacement liability. You can instead put that money towards RaamAudio or Dynamat sound deadening foam, that would make a far more noticeable improvement.

 

[jebinc]

"Tire" threads always seem so contentious...

 

[RZRZ]

A 1dB change is not worth a $300 increase in price and higher repair/replacement liability. You can instead put that money towards RaamAudio or Dynamat sound deadening foam, that would make a far more noticeable improvement.

I agree!

 

[Swampgator]

I would also pay nothing. Nobody in my area would repair my Continental tire, so I ended up buying 4 new Pilot Sport 4S (Porsche version)
I put up a post on another thread but bottom line the new tires are better in every way, including noise levels. Plus, they come with road hazard warranty that I can actually use in my area.
No brainer.

 

[dmd2005]

Acoustic tech is a gimmick. Unless you have supersonic hearing you probably won’t hear a difference over the wind noise from our Teslas. Type of tire compound from winters to all-season to summer performance tires makes a bigger difference IMHO.

If I had a choice I’d take the non-acoustic tire to save money in the long run. I had to pay $550CDN to replace a Continental tire on my wife’s X because nobody would take the time to peel the foam back, patch, and reglue the foam on the tire. I should have made the tire shop dismount the tire and I could have patched the tire myself.

I’ve had a little experience with using Nokian Hakka 9 studded, Hakka 8 studded, WRG3, R2’s, R3’s, Michelin PS 4S, Primacies, Conti DWS, Pirelli Sottozeroes, Pirelli Scorpions, and Yokohama Advans on my Teslas (I’m sure I left out a few other tires).

 

[cab]

I have a bit different take than artsci. I have seen some objective audio measurements of the foam-equipped tires vs non-foam-equipped, and on the sound meter, there is a measurable difference in noise. (See here.) However, that has some caveats:

1. The difference in absolute noise is pretty small. A few dB at most.
2. The frequency range where the noise is reduced are the mid frequencies (echo within the tire, sharper road imperfections). Lower frequencies (concrete rumble, larger bumps) are not really affected.
3. While noticable on the meter, whether it's noticable to your ears is very debatable. Many of the human testers say they could not tell the difference with their ears.

Some additional things to know about acoustic-foam-equipped tires:

1. They are more expensive than the non-foam counterpart. Given the small benefit to noise reduction, the value of that cost increase is debatable.
2. Emergency flat repair products that can seal a tire from the inside do not work on foam-equipped tires since the sealant cannot reach the puncture underneath the foam.
3. Many tire shops will not attempt to repair a foam-equipped tire with a standard inside-the-tire patch, as they do not want to accept liability for removing a portion of the foam. They will make you buy a new tire.
4. If noise reduction is the goal, start by using a different size and construction tire. As an example, moving from a Max Performance Summer tire in 235/35R20 (such as the Michelin Pilot Sport 4S) to a Grand Touring tire in 235/45R18 (such as the Michelin Primacy MXM4) will inherently reduce noise. The amount of noise reduction by this change will likely exceed what foam can deliver.
5. To maintain quiet tires, they need to be rotated throughout their life (whether foam-equipped or not). Some modern advise suggests that rotation is no longer necessary, but if you don't, all tires will get noisy on the back half of their life.

Agree with SomeJoe7777 above on all of this. It is that "singing" higher pitched frequency on some roads or the basketball like "ping" that the foam addresses. I wanted all the noise abatement I could get in the somewhat noisy Teslas so it is "worth it" to me - but the price premium does sting. I will say that Tesla still needs to invest in better structural damping, bushing isolation, sealing and better noise blocking in general. No amount of aftermarket sound deadener/blocker ever really seems to to do the trick in Teslas.

I'd like to think the Model S refresh could address some of this for that car, but I doubt they will add another door seal, or add a bunch of weight to the structure for absorption or somehow silence the battery compartment from being a big drum, or seal off the hatch area, etc. At best they might throw another 50 lbs of sound deadener/blocker here or there all call it a day.

 

[caesar305]

Just hit a tiny pothole going 35MPH and blew both passenger side tires on my M3P. Took it to a friend's shop where they repaired the rim (slightly bent) and they replaced my two tires. After driving on the highway I can hear a faint vibrating / humming (for lack of a better word) noise coming from the passenger side tires. Upon further research looks like there is a Tesla specific model and this thread confirms it. I've already driven it a few days so I can't take it back now to get it replaced but for me personally, I can certainly tell the difference.

On tirerack I noticed they have the same exact model except it says 'TESLA/ACOUSTIC' in the description for $340 each. If the thread is different from what @dfwatt says, I wonder what the effects may be, if any?

 

[dfwatt]

Just hit a tiny pothole going 35MPH and blew both passenger side tires on my M3P. Took it to a friend's shop where they repaired the rim (slightly bent) and they replaced my two tires. After driving on the highway I can hear a faint vibrating / humming (for lack of a better word) noise coming from the passenger side tires. Upon further research looks like there is a Tesla specific model and this thread confirms it. I've already driven it a few days so I can't take it back now to get it replaced but for me personally, I can certainly tell the difference.

On tirerack I noticed they have the same exact model except it says 'TESLA/ACOUSTIC' in the description for $340 each. If the thread is different from what @dfwatt says, I wonder what the effects may be, if any?

That shop did you a disservice. At the very least they should have informed you that there was a Tesla specific version of the tire before replacing it with a generic or non-Tesla specific version. The differences are non-trivial despite all the complaining that acoustic foam makes no difference. It does make a difference and additionally the tread is different. Nobody knows exactly what Tesla and Michelin agreed on in terms of how Michelin changed the tread on that version of the tire but it is at least a quarter inch wider and probably with different compounding. You should go back and confront the shop about their substandard practice. If paid through credit card you have a credit card claim against the shop due to their non industry standard practice.

 

[jebinc]

That shop did you a disservice. At the very least they should have informed you that there was a Tesla specific version of the tire before replacing it with a generic or non-Tesla specific version. The differences are non-trivial despite all the complaining that acoustic foam makes no difference. It does make a difference and additionally the tread is different. Nobody knows exactly what Tesla and Michelin agreed on in terms of how Michelin changed the tread on that version of the tire but it is at least a quarter inch wider and probably with different compounding. You should go back and confront the shop about their substandard practice. If paid through credit card you have a credit card claim against the shop due to their non industry standard practice.

Agreed. The tire shop should give you full credit for their error in tire selection.

 

[dfwatt]

Agree with SomeJoe7777 above on all of this. It is that "singing" higher pitched frequency on some roads or the basketball like "ping" that the foam addresses. I wanted all the noise abatement I could get in the somewhat noisy Teslas so it is "worth it" to me - but the price premium does sting. I will say that Tesla still needs to invest in better structural damping, bushing isolation, sealing and better noise blocking in general. No amount of aftermarket sound deadener/blocker ever really seems to to do the trick in Teslas.

I'd like to think the Model S refresh could address some of this for that car, but I doubt they will add another door seal, or add a bunch of weight to the structure for absorption or somehow silence the battery compartment from being a big drum, or seal off the hatch area, etc. At best they might throw another 50 lbs of sound deadener/blocker here or there all call it a day.

While I think everybody agrees that that Model 3 as it comes from the factory is noisy at speed due to wind and sometimes tire noise, we have a very different impression about the efficacy of various noise reduction approaches. We have taken at least 5 db if not more off the noise at 70-75 mph through several simple do-it-yourself modifications, so your claim that "no amount of sound deadener" makes any difference just isn't true. Admittedly, we've done a bunch of stuff:

1) RPM wind noise kit plus some extra neoprene tubing on glass gaps besides the front roof piece
2) dynamatting of all four doors
3) extra seals on doors and truck lid as discussed by BradHS
4) closed cell foam inside trunk and underneath side of rear package shelf
5) undercoating of wheel wells, and sound insulation on wheel well liners.
6) interior sun shades on roof and rear glass - these really helped too and kept the car cooler.

These are all discussed in various threads on this forum, and the other forum also - my estimate of the combined added weight from all these is probably ~35 lbs at most. Collectively, they have made a huge difference. We can now drive at 70, put the (driver modified) sound system at about 66% (two thirds of full loudness), and hear nothing except the music. It's quite a transformation.

 

[hcdavis3]

While I think everybody agrees that that Model 3 as it comes from the factory is noisy at speed due to wind and sometimes tire noise, we have a very different impression about the efficacy of various noise reduction approaches. We have taken at least 5 db if not more off the noise at 70-75 mph through several simple do-it-yourself modifications, so your claim that "no amount of sound deadener" makes any difference just isn't true. Admittedly, we've done a bunch of stuff:

1) RPM wind noise kit plus some extra neoprene tubing on glass gaps besides the front roof piece
2) dynamatting of all four doors
3) extra seals on doors and truck lid as discussed by BradHS
4) close cell foam inside trunk and underneath side of rear package shelf
5) undercoating of wheel wells, and sound insulation on wheel well liners.

These are all discussed in various threads on this forum, and the other forum also - my estimate of the combined added weight from all these is probably ~35 lbs at most. Collectively, they have made a huge difference. We can now drive at 70, put the sound system at about 75%, and hear nothing except the music. It's quite a transformation.

Great stuff as usual Doug. I’ve done the RPM on the roof, and the extra door seals from Basenour. It’s subjective as I don’t have a DB meter, but my car sure seems quite a bit quieter. The extra door seals mean that I have to close my doors with authority.

 

[jebinc]

Great stuff as usual Doug. I’ve done the RPM on the roof, and the extra door seals from Basenour. It’s subjective as I don’t have a DB meter, but my car sure seems quite a bit quieter. The extra door seals mean that I have to close my doors with authority.

The door seals also result in cleaner door jams. Worth it for that alone.

 

[hcdavis3]

The door seals also result in cleaner door jams. Worth it for that alone.

Thanks Jeb.