[Steve48]

Hi all, I am a couple of months into 718 Cayman S ownership and I really love this car. Lots of things to like...the one small drawback for me (and I knew this going in) was the amount of road noise coming into the cabin. I already disconnected the Soundaktor. Since this is my daily driver, I take a lot of calls on the road and the noise is definitely an issue for calls and having normal conversations with a passenger. Now I know this is a true sports car so I should expect cabin noise, etc...but I am looking at ways of "taking the edge off". I am considering putting in some sound deadening under all 4 wheel arches, and on the engine cover. I think doing this might make a reasonable difference. Many years ago I did all 4 door panels for my WRX and it worked wonders (Dynamat). What do you guys think? Worthwhile or don't waste my time? TIA

 

[gulshan]

Instead of going down the dynamat, quieter tires rabbit hole.. i would look for a cordless bluetooth one ear plug in unit that has the thingy to wrap around your ear so does not fall off. (used while jogging , treadmill use etc). The key feature to look for is it must have noise cancelling on "both sides" the earphones and the micro phone to remove the hiss..

 

[alf_17]

Watch and learn

 

[dreamer]

I think that’s a great idea except for one caveat. Your awareness of your surroundings diminishes greatly. Not being able to hear things coming from your periphery can be dangerous.

 

[jimmuller]

In our state it is illegal to wear headphones while driving. I don't know about earbuds.

My sweetie used to pressure me to wear noise-canceling headphones when I was commuting in my Triumph GT6. One morning I was stopped by a state trooper who "reminded" me of that law. I explained how they were noise cancelling, there was no music going throujgh them, then I handed him the phones. He looked at them briefly and said "The law says you can't wear headphones but it doesn't say anything about earmuffs. Drive carefully." He handed them back, I put them aside, and never wore them again in the car.

 

[Viffermike]

With due respect to the posters who recommend noise cancellation:

This is a commercial road car. It is really not that loud. This is not a race car -- or a motorcycle, on which tuned earplugs are, IMHO, a must to filter out white noise (mostly from wind) that can, over time, contribute to hearing loss.

Furthermore, as @jimmuller mentions, on- or in-ear headphones are illegal to use in many states in non-commercial vehicles.

 

[CaymanMatt]

As a clarinet in various ensembles, one thing that works for me is to use a single earplugs on the side where the loudest sounds are coming from - usually the trumpets!! That allows me to still hear the ensemble while reducing the overall sound level on the side that is affected most. I use Etymotic plugs but I'm sure there are others that are better or cheaper or ...
I haven't tried this yet in our CGTS but have considered it. FWIW, though, overall interior sound level seems to be dropping I'm presuming as the tires wear a bit. Soundaktor is of course unplugged.
YMMV

 

[Snrubel]

To get back on topic for you, please search on my userid and you can see some things I did (I have not written or documented them all yet). By far the easiest and best for the effort is to simply buy a box of bonded acoustic cotton sheets (get 1” thick) and cut it to fit the trunk area and on top of the engine carpet. You can easily get 6” in the trunk. It weighs very little, has no toxicity, and will absorb a ton of noise from the hatch. If you scoot your seat up you can prob attach some to the firewall too.

This will probably fix your issues enough to allow you to be happy driving and talking to other humans who happen to accompany you, but if you want to do more there is opportunity for hydrophobic melamine foam in and around the front, under the hood, behind the frunk, down in the footwell, etc.

If you want to get frustrated try to take before/after measurements to quantify the improvements. I tried to be an engineer about it but discovered it’s far more fun and productive to just be subjective since 99% of us lack the proper test environment and instrumentation to really get much from the quantitative measurement capability of an spl meter and/or an iPhone.

I think some posters are legitimately trying to be helpful with the variants of the “ear plug” advice, but none of us who are really trying to manage noise in our 718s are wanting to wear earplugs as if we were driving a mower. And I think everyone knows, or has a friend that knows, that some tires are quieter than others in a non-quantifiable, non-practical-to-use sort of way.

If we could get a real knowledge base of what works for noise reduction in Porsche sports cars that would be gold! Gold!

 

[718Niko]

Aye I'd try tyres change and putting one of those professional noise absorbing panels on the back shelve...
ear plugs might be dangerous as some have said.

 

[CaymanMatt]

Aye I'd try tyres change and putting one of those professional noise absorbing panels on the back shelve...
ear plugs might be dangerous as some have said.

I should qualify my statements about the Etymotics. Their intent is only to reduce sound, not eliminate it. Additionally, they reduce sound evenly across the audible frequency range. I am not 100% convinced of that last statement but overall they work well for reducing volume. You should still hear everything, it'll only be quieter.

 

[Steve48]

Thanks for all the advice everyone...I spent a few hours this past weekend doing some experimentation and am happy with the results. Like @Snrubel suggested, I put a bunch of sound deadening material in the rear area (on top of the existing carpet, so no taking apart of the rear bits), as well as putting on sound deadening material (Dynamat) in the wheel arch area (I took each wheel off, and the plastic wheel arch housing...put a little in areas that were bare metal, as well as some on the actual plastic trim). Overall, my non-scientific feeling is that it is about 20% quieter which is exactly what I was looking for. Still here the great noises from the boxer engine, etc...but it took the edge off. And next year, when I replace the OEM tires with Michelin Pilot Sport 4S tires, it might help even more.

 

[Steve48]

Wanted to provide a quick update. I have come to the conclusion that by far the biggest factor to my road noise concerns has to do with the actual type of road I am driving on. I went on a spirited 2 hour drive Saturday morning in the countryside (north of Dallas) and my god, the car was quiet as a mouse (relatively speaking). The roads in the countryside are much older (and def a different material) but I was shocked. Non scientifically, the in cabin noise was reduced by 75%, and all I heard was the great engine/exhaust note.. This is probably why many of you don't think road noise is an issue (ie maybe you have better roads where you live)? I am back on the terrible roads on my way to work this morning and the road noise is back in full force.

 

[DriveInHouston]

Texas chipseal is quite rough. I went biking around the Hill country and I was rattled and shaken to the bone.

 

[Treemagnet]

Texas chipseal is quite rough. I went biking around the Hill country and I was rattled and shaken to the bone.

Yes, we have more than our fair share of chipseal and it substantially amplifies road noise. Some so loud it's almost unbearable, top up or down. Perhaps it's less boomy in a Cayman, but my guess would be not by much.

New chipseal is the worst, so routes (bicycle & auto) are often varied based on re-seal age. Regardless, I'm sure you will find our chipseal smooth as a baby's bottom compared to our limestone heavy MTB trails. Similar to SPASM, my MTB has three on the fly shock settings (100% open, 70% open, full lockout). Regardless, I'm rarely in anything but "Comfort" (full open).

 

[DriveInHouston]

No shocks on my baby, just a steel touring frame (contrary to myth, it doesn't absorb much...).

 

[Grozk17]

I agree that road surface seems to be the biggest variable in road noise (purely observational) in my cayman. Some have noted tire make (I have Pirelli @11k miles) is a factor. I will say that my 2000 M roadster is considerably quieter on all road surfaces (it has performance all season tires with little tread ware) and no more sound deadening(other than a trunk with bulkhead between cockpit). So the hatchback area likely amplifies any sounds.

It would be interesting to do a head to head comparison between cayman and boxster with same road and tires.

 

[chester7]

One warning about sound deadening: I saw a Car Fix episode where they were replacing the fuel tanks on a Lotus Esprit because the sound deadening material on the tanks caused the tanks to rust.

 

[Naptown]

For me tire noise is the usual source of unpleasant sound in a car. Clearly affected by road surface. Engine noise is not so annoying in a sports car. My Michelin PSP4s are pretty quiet most of the time.