It's the tires and as suggested, a FAT tire is much more quiet... That means an 18 inch rim with sufficient rubber on it.

 

X-51 Coupe - you shouldn't hear the tires at all. Have new ones installed -AND properly aligned.

 

+1. Just to clarify it some more... "Fat" Tire = higher profile tires. Not fat/wider tires. Fatter/Wider tires can give you more noise too.

For the OP - I think we should not be comparing/expecting the same noise level as an A8. Apples and Oranges.

 

ok, follow-up here, when i put on 18" rims,(looking at a set of speedlines, 3 piece, totally refurbished/polished) what size tires would i use, they are 8 and 10x18, and will they fit over stock brakes? and ET's are 52 and 61

 

Mine is loud on only some highways. Most of the time it is quiet. I have new PS2s on mine. ON some interstate though it is very load. Sure if you went to really skinny tires and smaller diameter rims the noise would go down but who wants that???????? I like low profile Fat tires on mine.

 

LOVE the sound of a nice engine

 

I gave up last week after my Sirius subscription expired. New tires are better than old, good roads are better than bad, etc. etc. but bottom line, there are lots of times when the road noise just overwhelms anything you're trying to listen to. So, next up, I'm going to try Pandora on my iPhone run through these:


Best,

 

I've driven the three 997's I've owned (2 cabs and a Targa) over 40,000 miles and agree that the main contributors to road noise are coarse pavement (eg Interstate 5 through most of Oregon and Washington) and tires that are over half worn. On one trip from LA to Vancouver I wore foam earplugs to reduce the fatigue. It worked wonderfully. My cabs were a little noisier, but not much different. There is added rumble of noise over the top as well as through the side of the top behind the rear side windows.

 

My C2S is actually not that loud. I have significant road noise on some concrete surfaces where they realy put some texture on it to move water, otherwise not bad. I have bridgestone RE50's on the car (came with them from the dealer) and they are pretty well behaved.

You would have to think the car contributes somewhat to road noise (insulation level, proximity to road, etc.) but the bigger factor must be the tires...as the interface between tires and road is what is making the majority of the road noise. I would consider driving other 997 owners cars that have different tires...find one you like.

 

As tires wear and your going to replace them anyway. Spend the cash and get an alignment. If the alignment is really off, you might be adding extra friction which translates to noise. Especially on older tires.

 

I have brand new Hancooks on my car & when I hit concrete freeway the road noise is insane but normal pavement is almost nothing. I travel the worst 30 mile stretch of freeway in Southern Oregon 1/2 fresh pavement & 1/2 concrete old road when I see that concrete coming up I have to grit my teeth to get thru it, the noise sucks.

 

I had six year old 50% tread Michellin PS2s. They felt like i was riding on frozen hockey pucks on the I5. And they were loud. I replaced all fur with RE-11s and the car quieted down a lot. The ride was much much smoother too.