was wondering how a flowmaster 40 series muffler sounds on 89 firebird l98 my local shop said that it would be batter for the car than 80 series any thoughts

 

Here's an example of an 80's series on a 3 inch exhaust with a catless y-pipe

http://www.youtube.com/watch?v=z1gJ8...7&feature=plcp

 

I have heard the 80 series before and like it was just wondering what a 40 series would sound like

 

There appears to be more than one 40 series muffler offered by Flowmaster .Scroll down the list to see .
http://www.flowmastermufflers.com/index.php?cat=1
Heres a sound test on the super 40 =
http://www.youtube.com/watch?v=WwOFCGYlZvQ
The only problem there could be is running it in the traditional location which the 80 series is designed to do.

 

My co worker has one on his 91 RS 5.0 and sounds good. I dont like the 3 inch 80 series, a lot of popping noise as to why a lot of members dont like the flowmaster. I run the 2 1/2 80s flowmaster on my car and love it. On stock manifolds at least thats as big as you need anyway. I have video of my buddies 87 Z28 355 cammed with flowmaster 40 2 1/2 but its not going to be near what a stock l98 sounds like.

 

An original 40 Series should sound better but you will lose the dual tip look. If you don't want that, try the 80 Series that is 3" in and 2 1/2" out. The all 3" one that comes with the AT systems doesn't sound nearly as good and has unfortunately turned alot off to Flowmaster here.

 

The 40 series always sounded hollow to me. My 80 series had a hollow idle. But not when you rev'ed it or under heavy acceleration. I always liked my 80 series.