storii

^^ This is interesting. I will have the PS4S mounted tomorrow and this weekend is supposed to be nice and warm. I will report my impressions by Monday.

Audioi

Take along your SPL app!

smohr33

Getting PS4S mounted tomorrow as well on my BGTS. I did about 8k miles on Goodyear Eagle F1's that came on the car, no complaints until I caught a nail in the sidewall rendering a rear useless.

With the Goodyears dead, I found a set of wheels with new PZeros locally, and have had them for the last 3k miles. The PZero is stiff, terrible in cold weater, and LOUD. I can't wait to get rid of them. Expecting a big difference in noise and comfort with the PS4S. I'll report back.

Audioi

Patiently awaiting results!

storii

Okay, according to the dB meter app that I used, the PS4S's were not any quieter than the P Zeros. The phone with the app sat on the console against the heater/AC controls picking up all the noises in the cabin. The top was up all times. The conditions were far from optimal for a fair comparison, though.

• P Zero: F235/35/20 - R265/35/20, about 30% tread left, driven in 37-39F ambient temps
• PS4S: F245/35/20 - R275/35/20, brand new, driven in 46-48 ambient temps

At 40 mph

• P Zero: up to 65 dB
• PS4S: 68-71 dB

At 65 mph

• P Zero: 78-80 dB
• PS4S: 78-83 dB

According to the dB readings alone, the cabin noise level with the PS4S's were slightly higher. However, it was not only the tire noise but included the wind noise and the engine noise that must have made considerable difference in the readings. As far as my personal impressions go, they both sounded pretty much the same.

A noticeable difference I felt was that the PS4S's were considerably softer than the P-Zeros. Going over the road joints, the PS4S's absorbed the shock much better than the P Zeros. They didn't sound as harsh as the P Zeros did when going over the joints. But again, the PS4S's are brand new while P Zeros were worn much more. I will have to wait until I do a good amount of top-down driving to come to any kind of conclusion. However, at this point, I feel the tires may not be as big a factor in terms of the overall cabin noise level. YMMV

Audioi

Thanks for your feedback. I am sure the Michelins will come into there own once the temps climb.

storii

I experienced something remarkable today with my new PS4S that I think is worth reporting here.

I went to a PCA event today and the meeting place was about 65 miles away from home; 70% highway and 30% local roads. Heading to the meeting place this morning, the ambient temps were in the low 50's and the PS4S's were performing exactly as in my last report: while the performance level of the PS4S's were superior to the P Zeros in every way, they were just as noisy as the P Zeros except for when going over the joints. The front PS4S's will tell you the joint is there and how big or small it is but won't give you the slapping noise that the P Zeros would give.

Now, on my way home in the afternoon, the ambient temps were in the low 70's. I was driving with the top down on local roads and noticed that the tires seem to be quieter. I was telling my wife that the car seemed to be quieter with the top down. I reasoned that perhaps the noises resonate in the cabin with the top up. Going onto the Parkway, I raised the top as we were going through the toll booth. I immediately noticed that the car was remarkably quieter than in the morning. After a while, I turned on my dB meter app. The readings at 70-85 mph were 71-73 dB, considerably lower than 78-83 dB that I got at 65 mph+ in the high-40 ambient temps a few days ago. I realized that the temps play a HUGE part in the level of tire noises.

I bought my car on the last day of September last year with a set of brand new P Zeros. I didn't notice any excessive tire noise then. I sold my wheels with the tires and bought a used set of different wheels with worn P Zeros in February. Those were noisy but I only drove on them in the low 40's. So, to be fair, the PS4S's may very well be as quiet as the P Zeros in the 70+ ambient temps. But I have to take back my comment in the earlier post that the tires may not be as big a factor in determining the overall cabin noise level. They do make a difference. Once I realized how quiet the cabin was, I dropped to the 4th gear and kept the engine at 4500 rpm and up and enjoyed the music of the flat 6 and the immediate throttle response all the way to home.

Audioi

storii

It looks like the ambient temps have a lot to do to the level of tire noise. I would give a chance to the P Zeros on a 70+ day and see how they perform before splurging on the Michelins. My guess is, as far as the tire noises are concerned, the PS4S's and P Zeros could be pretty close under the same conditions.

smohr33

Ok so my PS4S have been on for a few days and in my opinion they are much quieter, and ride much better than the P Zeros. I could hear the difference in noise immediately, no comparison. I'd take the dB meter readings with a grain of salt, there is engine noise, wind noise, hvac, etc... no way to isolate noise being produced by the tires only. Ride is definitely softer over bad roads. More of a "bounce" than a "bang" when compared to the P Zero. Grip felt better in cold weather, the P Zero always seemed really stiff in the cold, much more confidence with the PS4S. So far I'm very happy with them.

Cosmo Kramer

I just put a new set of Michelin Pilot 4s on my BMW 640 Gran Coupe. The stick well, ride well, and are reasonably quiet.

I will try them on one of my P cars when I need a set.

Hoss33

Hyped

storii

I also have the 245/275 combo PS4s on my car which is equipped with PASM. Hope these pics help you.

Hyped