I've been 84-86db at every event, but they typically read from the drivers side, and I aim mine towards the passenger side so it isn't near the diff.

I'd expect maybe 88db if it was straight down. (I think this is at 60'ft)

The booming is quite loud inside the cabin. I DD with the dump on and have considered running a pipe out of the back to save my ears. It's loud enough I sort of expect there is a possibility of hearing damage if you drive it 365 days/yr like I do.

 

Thanks for the updates! I am considering doing this for the weight reduction to $$ ratio, but sure do hate to cut the stock exhaust.

 

I got a second stock exhaust for a case of beer. Look around, there are always people either giving away or selling their stock exhausts for cheap.

 

Weather conditions, site, and meter locations affect db measuring.

Locally, the pad is flat and not a lot of anything around for a ways, and I have the pipe exiting straight under the car and I was measured at 94 db's and the limit is 92 db from 50 ft. I tried running a turn down, and reduced it to 92 db.

 

I just installed a Berk 63mm high-flow cat with the exhaust mentioned in the very first post in this thread. It's loud! I felt ok driving with this exhaust and the stock cat on the street as long as I drove a little more conservatively. The addition of the HFC makes it quite a bit louder and boomy. People have stated that adding a HFC to any open exhaust makes the off-throttle droning better - that's true. But it makes this exhaust louder in every other possible situation. Yikes.

For reference; I drove for about 6 days with the Berk in place with the stock exhaust. I couldn't detect any change in sound at all. Now, it did positively stink as it broke in, but most exhaust components have this issue.

No complaint about the Berk though, it's a VERY well made piece with beautiful metalwork. Just be warned that it'll increase sound levels on the cut stock exhaust. I'd say the shorty exhaust with a Berk HFC is about comparable with an original Invidia exhaust with the stock cat.

 

Thats weird, I have the exact same cat and find that it might be a touch louder at WOT but that its actually quieter everywhere else.

 

Did you gain any throttle response? Specifically what I mean would feel like a lighter flywheel. Does the engine rev up quicker? This may be noticeable when launching or rev'ing in neutral.

 

Maybe I'm over-compensating for the placebo effect but I'd have to say a very minimal change. It sure sounds like it revs quicker on blips, but that might just be because it sounds like a crazy sportbike exhaust.

I think the incremental increase in loudness was just enough to push me over the "I'm too old for this s**t" threshold. It sounds awesome on the track, but even people that didn't know I'd changed anything came up to me and asked why my car was louder than it used to be.

 

Yea its definitely louder when your getting on it (ie autox) me and friends have noticed that... but it still sounds quieter to me at lower RPMs cruising around (my fiance though cant tell the difference... I wonder if the cat changed which frequencies were louder and quieter, and the frequencies I am more sensitive to are less now but the ones you are mores sensitive to are louder now, everyones ears are different.

oh and Im only 22 so the "im too old for this S**T!" effect hasn't hit me yet

 

We just tried this; what a great mod.

It's not as loud as I'd feared, and there does seem to be an improvement in throttle response.

Packwood NT is next week; I'll let you know how it does on sound.