Road noise in fr-s

[Gforce]

Originally Posted by nextcar

If you are adding 200 pounds, you are doing it wrong. I am amazed at how many people misunderstand dynamat and the like... small applications are as effective as full coverage without all the weight. You are trying to dampen the resonant frequencies of the metal, not cover it or make it heavier. Light weight fibrous insulation does a much better job at absorbing sound than dynamat once you have controlled resonance.

When I see a car that has stripped the interior and done full coverage of dynamat or a similar product, I shake my head at the monetary waste, excess weight, and lack of fundamental understanding...

I'll just don my flame suit and leave the thread now...

You are of course correct. There are a few places where a bit more sound deadening would make a big difference. The footwells under the felt you refer to that the factory used, for example. The door skins. The rear parcel shelf and inside the rear fenders. I'm betting there's almost nothing on the underside of the roof and it is paper thin high strength steel. I would never add any weight up there regardless of noise. Dynamat works by changing the weight of the steel panel it gets stuck to. Felt works by creating interference waves inside the tiny air passages in the felt. Totally different process. Dynamat type stick on sound isolation is very heavy per unit of sound reduction. Factories use an asphalt pad essentially partly melted onto the panel to change the frequency with which it vibrates. Heavy and effective.

With my Supercharger I know for sure removing the underhood sound proofing makes no difference whatsoever.

[Tcoat]

Originally Posted by Gforce

The P Zero A/S plus is newer than the Michelin. In 2013 when I bought my Michelins the equivalent Pirelli was not so good. I drive about 10,000 miles a year split equally between summer and winter tires. Let us say I do not try to save my tires, smoke em regularly because after 5 years from the DOT stamp they're no good for grip anyhow.

No question the Michelin is the better tire in cold weather and nearly as capable as the Pirelli when used as a summer tire. Snow grip is pretty impressive for the Michelin when you consider how grippy it is in hot weather. Notice the tiny biting teeth in the tread grooves? They really work on snow if it's not too cold.

Let me defend the factory choice of the Primacy. A very light tire with good grip wet or dry. The Primacy suits the power level admirably. Doing all this again I'd modify the shocks and springs before I laid out good money on replacing the fairly good Primacy.

UMMM I don't think you are talking the same tires as I am. The Pilot Sport AS3 PLUS just came out about a year ago so you didn't get this version in 2013. They are in no way comparable to their predecessors the AS3.

http://www.prnewswire.com/news-relea...300203155.html

The only thing I found that put any AS performance tire (and many summer ones) was what you posted from Tire Rack. Every other site I checked put the Plus well above the Pirelli. Like I said though I do not have an opinion on the Pirelli since I have never owned them.

I didn't mind the stock tires at all other than they were noisy as hell and expensive as shit to replace. The only reason I replaced them now was they were getting to be dangerous to drive on. since they had so many highway miles on them.

[venturaII]

Originally Posted by Gforce

My point is that there is no solution. Subaru knows all about road noise. If they thought it could be reduced without spoiling the car they would have.

Fitting higher performance tires is a bit of a no brainer but increases road noise and uses more fuel. Sometimes the factory does know better.

So, fitting higher performance tires to gain traction is acceptable, but fitting lower performance tires to make it quieter isn't - even if noise is the primary complaint. LOL What a stunningly narrow view of the world.

[Tcoat]

Originally Posted by venturaII

So, fitting higher performance tires to gain traction is acceptable, but fitting lower performance tires to make it quieter isn't - even if noise is the primary complaint. LOL What a stunningly narrow view of the world.

That is even if assuming that higher performance tires have to be noisy. They don't.

[venturaII]

Just for the sake of argument, let's say they do. Fitting quieter tires would thus improve the car from the owner's perspective, not ruin it.

[Gforce]

Originally Posted by venturaII

So, fitting higher performance tires to gain traction is acceptable, but fitting lower performance tires to make it quieter isn't - even if noise is the primary complaint. LOL What a stunningly narrow view of the world.

Anything you want to do is ok by me. These cars don't need any improvement to be enjoyable.

High traction tires are a bad idea unless you also fit forced induction. I'm coming around to the idea that the factory chose very good tires in the Primacy. Unless you have a lot more power fitting grippy tires spoils the car somewhat. I still enjoy driving my BRZ on winter tires, even with 260 hp. I'd fit better shocks before better tires, if doing this again.

Trying to reduce the road noise is pointless and impossible to achieve by any reasonable method, or I would have done so by now. The road noise is appalling, but then the engine noise in a Cayman is inexcusably loud. I can tolerate the road noise in preference to Porsche engine noise. Cars used to be quite noisy. The BRZ is much quieter than say a 1966 Triumph GT6 which it otherwise closely resembles.

[Gforce]

Originally Posted by venturaII

Just for the sake of argument, let's say they do. Fitting quieter tires would thus improve the car from the owner's perspective, not ruin it.

Well, no because the car would still be too noisy and the quieter tires would handle very poorly with the stiff springs and shocks the stock car comes with. So no improvement along the lines intended and making the car otherwise a lot worse.

Certainly, any owner could do this but it would be a mistake. Even the quietest available tires would be very noisy. The Primacy is already a quiet tire.

Since you want to argue.

[venturaII]

Originally Posted by Gforce

High traction tires are a bad idea unless you also fit forced induction.

Another outstanding piece of advice. I need to write this stuff down...

[Spuds]

I found that the underpanels reduced road noise a bit at highway speeds. But I don't have rear seats so results may vary.

[Tcoat]

Originally Posted by Gforce

Well, no because the car would still be too noisy and the quieter tires would handle very poorly with the stiff springs and shocks the stock car comes with. So no improvement along the lines intended and making the car otherwise a lot worse.

Certainly, any owner could do this but it would be a mistake. Even the quietest available tires would be very noisy. The Primacy is already a quiet tire.

Since you want to argue.

I am on RSR Super Down lowering springs, stock power, and now have the gripper and much, much, MUCH quieter tires. Other than having to work a little harder at breaking the rear end loose do not feel for one second that the handling has been made worse. In fact I really like the improvement in handling a have in my daily driving scenarios. The noise is easily reduced by well more than 50% and I am now hearing rattles and clicks I have never heard in the 3 years I have driven it. I spend a minimum of 14 hours a week driving it with 98% of that time at high speeds on the highway so am pretty sure I know that it is much quieter now then it was on the stock tires (we won't even bring the noise the snows made into the debate). This assertion that the car can not be made quieter with different tires is not realistic.

[JDM4E]

Originally Posted by Gforce

Trying to reduce the road noise is pointless and impossible to achieve by any reasonable method, or I would have done so by now.

Not true at all. Many threads here, even with dB measurements says otherwise. For a few kgs of weight you can make the car significantly more quiet.

[TommyW]

If quietness is a priority probably best to choose a different car.

[Gforce]

Originally Posted by TommyW

If quietness is a priority probably best to choose a different car.

Exactly. Subaru built a car that is exciting to drive, all of the time. The noise forms part of the driver engagement which produces that excitement. The steering feel, shift action, the lively suspension and the very busy high revving engine all make their contributions.

It doesn't matter that the radio is crap, just doesn't matter.

[Gforce]

Originally Posted by Tcoat

I am on RSR Super Down lowering springs, stock power, and now have the gripper and much, much, MUCH quieter tires.....The noise is easily reduced by well more than 50% and I am now hearing rattles and clicks I have never heard in the 3 years I have driven it. ....

This is impossible to achieve. I'm not sure you even know what reducing noise levels by 50% even means.

Do you?

Glad to see you have successfully addressed the Achilles heel of this car, not enough rear grip.

I fixed this by fitting softer rear springs, MCA traction aids and a stiffer front roll bar.

Then a Supercharger so I can decide when the back gets loose, not the car.