I just got back from the Historic car races in Monterey, and had a chance to evaluate the soundproofing project to date. On the open road with the top up, the stock head unit was usable to 105 mph. I went most of the way with the top up because of the heat, but up to about 85 mph, it is quite pleasant. The wind noise from the top is not a curable item, but I think if the other sound can be managed, it won't be intolerable. I will be testing some new material in the trunk, floor, and firewall next week to get some readings. The trunk area, at least at part throttle, is an area that needs a lot of work, and the induction roar through the firewall can be helped, although this is proving problematic with all the wiring and air bag fittings. However, before we ship kits, all will be figured out and I'll have real life readings. I have a high end decibel meter, and noticed that the radio shack models I've checked it against all read lower, so we'll just use comparitive reduction for our figures. Repeatability is the key here.

As an aside, all the way from Colorado to LA, up to Monterey and back, and the only other S2000 I saw outside of a dealer was one black one in the pits at the races. Somebody explain that to me. And, while in Carmel, I saw two Ferrari's and three Porsche's every block! No kidding! So many it looked like Mercedes in Newport Beach! But, it gets better. A guy in an F55 stopped me and told me I had a great looking car! Pretty cool.

 

Thanks for the update! Glad that you are making progress. By the way, a really RARE car is a chevy in Newport Beach!

 

Hey, I was there too.... how come you didn't see my car?
It was a great weekend...

 

I recently drove an S2000 with the trunk/behind the seat area stripped out. Even with the windows down at 75 mph (top up), there actually seemed to be more noise (and of a more irritating pitch) coming from the trunk area!! Must be a hell of a resonance chamber in there.

UL

 

Any progress? How much of a reduction in dB level are you aiming for at 80 mph with top up? BTW, what is the baseline(stock) dB level reading at ~80 mph with top up on a smooth asphalt road?

Thanks!

 

Hey chipperman -

Wasn't sure what kit you were talking about, but just did a search, and am extremely interested. I hope this post, or a facsimile of it, ends up in the group buys forum soon - I am interested, to be sure...!

 

Yeah we're all waiting on further details.

 

Ditto! Have a feeling this will be my "winter" project. (one of em at least, ha)

 

Chipperman, I've been following your soundproofing threads with interest, but I have one question.

I know the kit hasn't been finalized, but do you have a rough estimate of the cost range you're targeting? I know it's not going to be cheap, but are we talking about something around $200 or more like $500?

 

Although it varies with the road surface, on a fairly smooth road at 80 mph with the top up, the level is about 85 db. The quality of the sound is important , too, as a phone or a backup alarm may not be really loud but may be really annoying. I'm still working with the trunk area at present, stay tuned.