Does anyone know why the S has more road noise than the Turbo S? I am referring to Harry's Garage on YouTube, who measured road noise in the Carrera S and the Turbo S. The Turbo was significantly quieter. Curious as to why, as you would expect the Turbo's wider tires to contribute to more road noise than a standard S.

 

Maybe more noise escapes the wheel vents on the Turbo

 

maybe that S was a "monday" car?

 

I think he speculated that the Turbo S has more sound deadening. He also complained about the noise in the base Carrera.

 

Maybe! But unlike most of the (entertaining) clowns on YouTube, Harry is the real deal. He used a sound level meter to measure 80 dB in the S at 60 mph. That's a lot! 80 is enough to damage your hearing over a long drive!
For comparison, an AMG GT R was measured at 69 dB by Auto Decibel, a massive difference! And the GT R is more like a GT3 or GT2 than a normal 911.

 

I think the Turbo S has the noise insulating glass (Option VW4) while the Carrera S didn't.

 

Ok right, I guess that's "Lightweight glass made of compound glass and acoustic film for front and rear windshields and door windows. The lightweight glass offers a weight savings of over 4kg and improves interior acoustics by minimizing external noises such as tire and wind noise."
Does it really reduce noise levels that much?

 

It is an option for both the Turbo (S) and the S. I guess he may have driven the Turbo WITH the option, and the S without it; I have the Noise Insulated glass and I hear hardly any road & tire roll.

 

I wish I could have gotten the glass but cabs don't get it. My Cab is super loud on the highway at 80mph but I expected this.

 

Aha, thank you guys, much appreciated!
With the Cab, you would want to be top down most of the time anyway, I imagine.

 

The tire pressures may have been different on the two cars as well. It was not an empirical test where all inputs were equal.

Glad I selected the noise-insulating glass for my inbound C4S though.

 

Most likely tires. I don't recall that either of his tests indicated which brand of tires the cars had.

 

Maybe, but his analysis of TTS road noise compared to the C2s is completely useless. If the TTS had insulated glass and the C2S didn't, then the analysis is worthless. Nevermind what brand of tires or tire pressure he's running.

 

Harry also complained of a harsh ride. I really think the issue was tire pressure. These cars are always set with 45lbs+ from the dealer, the rental office and whereever. There is night and day difference in ride compliance and noise when setting comfort pressures.

 

Just the placement of the Intake Air Ducts on the Turbo will cut the interior noise level significantly.

I placed sound deadening on the wheel well panels, behind the plastic wheel well skins. It has made a huge difference in the amount of intrusive tire noise. At drivers ear (middle of car) level I'm down to an average of 67.7 dB on a local 2 mile loop at between 25 and 50 mph. Previously it was 74.4 dB. By way of comparison our BMW X5 in 100% electric mode (quiet) is 56.7 dB and my previous DD a Jeep Grand Cherokee was 64.8 dB.

Goodyear F1 Tires running at 33 PSI Front / 38 PSI Rear.

I'm using a BAFX3608 dB Meter FWIW. https://bafxpro.com/products/bafx-pr...ed-sound-meter
.


Before

After