docfink

Just picked up my GT4 from a dealer near me 6 weeks after getting it in Zuffenhausen. Maybe I'm nuts, but I swear the exhaust/engine sound is quieter now. The overrun pops/grunts seem more subdued.

Is something done at US Customs/Porsche PDI to the tune to quiet our US cars?

stout

Can't say, but can say this: If anything, U.S. Porsches may be louder than their European counterparts. I don't know which ones, but remember a German engineer divulging that the 987-1 Cayman S (maybe with sport exhaust?) could be louder in the U.S. and that they took advantage of that.

YMMV according to model and market, but my sense is that my GT4 is every bit as loud as the European and US press cars I tried, if not louder. Sometimes, I can't believe it's legal. That goes double for the 981 Spyder.

trebien

I drove 11k kilometers in Europe and got quite used to the sound.

It's been back in the states for a month now, and I don't think it's quiter at all.

But I WILL say this... I don't know where you were, but the roads in the US tend to be more "open"... be it larger spaces for walls, wider streets, less building encroachment, etc.

This would cause less echo from closer surfaces. Just a thought.

The Pope

I think what he was trying to say is that his own car seems to be sounding quieter here in the US as compared to when he drove it in the EU upon European Delivery. Methinks it's mostly perception as the US has more vast and open roads whereas in Europe roads are more confined and car sounds may reflect off buildings and wall a bit more.

Radiantm3

Or maybe the exhaust valves are stuck closed?

stout

Suspect you may be right.

Also could be.

Farani

In regards to the exhaust valves, in my 981S, it was very obvious when they opened up. The sound at idle was noticably different. Are you noticing any difference at all at idle when opening them?

Ynot

Probably not, your GT4 is build to US spec, they don't change anything at the PDI. I know when I did ED, I took out the emergency kit and hazard triangle with me b/c they will take the hazard triangle and replaced the emergency kit with bandaids. It's probably the wide and open road that makes your exhaust sounds quiet.

Dr. Ferdinand

+1, had to do the same during ED delivery as the warning triangle and emergency kit get chucked. The triangle was a heavy dude as it was filled with sand.

OP - maybe stretching it here, but other than perception, could it be attributable to the fuel grade? If you used 100 (RON) Octane in Europe and you are on the West Coast where you don't even get the top US octane (91 AKI, or [RON+MON]/2), that might account for some of what you are experiencing (slight loss of HP and perhaps aural divergence). You have to had some incredible butt dyno and hearing to detect that though

docfink

Thanks for all the insight. Maybe I am crazy...driving it more and it sounds fine--and plenty loud. I'll just enjoy it. Thanks again--

John@Fabspeed

I have a client of mine over in Europe that a few weeks ago gave me a call and swears (to the point of buying our exhaust tips) that the dealer switched out the tips for an updated version and it killed the sound of his car. No change in anything else while at the dealership. Food for thought...has anybody else encountered something like it?

Also, the Boxster Spyder has been known to have some more burble/overrun from factory than the GT4. They have the same exact exhaust systems and engine, but different ECU programming from factory. Therefore ECU programming could potentially play a factor as well.

user1029

Maybe they snuck some catalytic converters on

I foresee race headers in your future

Georound

I read a post recently suggesting lower octane could change the engine characteristics enough to notice including sound. Isn't the octane significantly higher in Europe, especially us in California at 91.

Dr. Ferdinand

Yup - that was my theory in post 9 above ^^^

neanicu

I fill my tank with this only,I buy bulk...no gasoline.