iborg

I know this sounds a bit wrong but I have a roadster and I'd like to quiet the road and wind noise at speed when my top is up. I plan on adding a 3 inch downpipe but understand that won't really add to the noise unless I'm on the gas.

Thoughts?

dh53

For road noise you will want to take off the door panels and the pull up the carpets and put on any one of the commercially available sound deadening mats. An alternative is to go to the hardware store and buy window flashing tape. Cover everything you can, especially large areas of sheet metal. Doing the doors should give you the most bang for your buck.

For wind noise carefully check all the window seals, then maybe stitch on another layer of convertible top material, preferably with a little open cell foam between the layers. It is all about isolation, getting as much stuff between your ear and the wind as possible.

iborg

I'd really like a headliner between the soft top but those aren't typically available. I'd love to find someone with one for ale or at least a pattern. I'd try to make one as a last ditch effort.

dh53

You could get pretty far down this path and find out it doesn't work very well so you might want to do a quick and dirty test. It is a little low rent but you could use tape, rope, bungee cords, or whatever it takes to hold a thick blanket up against the top as a temporary headliner. Take it for a spin and see if it reduces the noise enough to warrant spending any more time & effort on it.

carkarl

Your question made me want to share my experience from a '99 A4 avant where I also started entertaining thoughts about road noise and cruising comfort.

When my tires were nearing end of life, I chose replacements that had great noise ratings on tirerack. I replaced all the engine and transmission mounts, most of which were pretty rotten with age and I assumed transmitting more vibration into the unibody. Eventually, I bought a big box of dynamat-extreme and set about treating my car. I opened up the doors, scraped out all the (now brittle) factory deadening, and replaced it with a more generous helping. I also treated the whole rear cargo floor and spare tire well where there was bare sheet metal easily found under the removable floor panel. I never got around to pulling up carpet in the front nor tearing apart the rear hatch. Those seemed like too much labor and possibly too much collateral damage if I made mistakes taking it apart.

Even then, the change was pretty dramatic at cruising speeds. It was quieter and I could obviously listen to music at lower volume levels. But, unfortunately by reducing some of the "white noise" of the wind through the doors, the remaining noises became more annoying and mechanical in nature. I did some experiments like cruising at 70 MPH on a flat highway and then cutting the throttle, disengaging the clutch, and even putting it in neutral. From this, I got a clear idea which parts of the sound were coming from engine or transmission. I also did the same thing at some lower speeds so I could compare cruising in two different gears. There was some obvious gear lash when maintaining speed, but by far the main noise was the engine and exhaust and it was not going to get better without something crazy like a transmission swap to get taller final gears. I started to realize that my mind was going down a path where I was never going to really be content with the cruising noise again...

Long story short, I finally sold my A4 in spite of its sentimental value, and we replaced it with a new Q3! It isn't quite as fun to me as the old A4, but it is just as capable for our mountain trips with cargo, and much more comfortable as a highway cruiser. The improvements in sound deadening and engine noise are pretty substantial when comparing cars of such different vintage, and that's even with the Q3 being an older design due for replacement any day now.