Quote: Originally Posted by DBLTKE How do people think the 80 series is loud? My friend has a 2.5" 80 series catback with hooker 2055's on his L03 firebird and we're baffled at how stock sounding his car is, yet my car was louder than his when I only had some off-brand catback. I can't even hear his exhaust when I'm cruising behind him with my windows down. Old loudness data from my TPI 350.... Stock manifolds and Y-pipe, no cat, Flowmaster American Thunder (80 series, 3" in, 2.5" out). Idle 72 dB 70 mph 80 dB WOT 88 dB Idle is a cold start inside the garage. 70 mph is in O/D. WOT is measured at 5000 RPM under load. "A" weighted dB scale used. All are done inside the car with the windows closed, radio off, A/C set to OFF. Stock manifolds and Y-pipe, Catco cat, GMMG with oval tips. Idle 73 dB 70 mph 78-80 dB WOT 90 dB Now the GMMG setup is a loud exhaust. It's as loud with a cat at 4000 RPM as the Flowmaster without the cat was at 5000 RPM (88 dB). However, I wouldn't call the Flowmaster a quiet muffler at all. You would definitely hear me rumbling down the road when the Flowmaster was in there.

I chose the idle, 70 mph, WOT figures with the A weighted dB scale because that's what Car & Driver uses. I figured it would be neat to compare with other cars.

My 80 series (43083) on my stock L98 was not quiet. After headers and 3" exhaust, it was loud. Not SLP loudmouth loud, but it was loud. I now have a full 3" exhaust with a powerstick muffler on my H/C/I L98. Now that is loud.

I have a series 80 in my 91 Z28..its only the 305 tpi and i have dual cats and mine is rediculously loud..I've been pulled over multiple times because its so loud and ive only had it for maybe a year. Im sorry to hear your bad expierences.

Just in case it hasn't been said, the 40 and 80 Flowmasters have the same internal components but the 40 has 1 inlet and 1 outlet and the 80 has 1 inlet and 2 outlets and sits sideways (Crossflow).Thats it. Straight from Flowmaster.The 80 was made to fit our Y pipe single pipe cars. The 40 can be run with a dual exhaust. At least that's what I was told. Know wonder the 40 sounds louder and has a slightly different tone.Buy the way I run a 80 series American Thunder 3 in. pipe with a Magnaflow high flow cat and I get compliments all the time. I like it allot. Hears a link to a page of all Flomasters mufflers and it also shows the internal components. http://images.google.com/imgres?imgu...atAOJi8D1Awand heres a video link to a 80 Flowmaster http://profile.myspace.com/index.cfm...deoID=23636387 and here's one to a Magnaflow http://www.metacafe.com/watch/yt-wi4...ow_exhaust/and heres one to a Powerstick http://www.youtube.com/watch?v=7TkhsB3TGio&NR=1

I have 4-1 Hedman Headers the camaro fitting ones, cant remember the number anymore. The 2.5 inch H-Pipe all the way to an 80-series muffler. Granted the engine has a pretty lopey idle, the car sounds like the world is coming to an end when you rev it up and I can feel the exhaust hitting my chest all the way down the driveway about 50ft away. The idle is aggresive and loud. Sounds mean and would scare off most tuners for sure. I LOVE IT!

383 stroker!!! Gotta love it. I'm hoping that will be my next motor.

I've had my Flowmaster 80 Series on my car for about 7 years now and I love it.
I went with a high output CAT and 3" pipe from the cat to the muffler, and of course 2.5" tips.
It is kinda quiet when idling around, but when ya get into the 2500rpm range it really can be heard.
Cruising at 65 or 70mph it's loud enough to where you enjoy it, but not too loud.

Have a friend get in the car and rev the ngine a few times up to 5 grand while you stand behind the car. You'll be impressed.
I'm sure there are louder and better mufflers out there, but I think it's the best bang for the buck.