Backpressure is from the header/cats...not the mufflers. Mufflers are for sound alone. Hence, they muffle(r) sound.

Backpressure is a myth. You don't want backpressure for performance...maybe for emissions like the way an EGR performs...you want less backpressure and a higher exhaust velocity to create a scavenging effect pulling more air/fuel into the combustion chamber for more power.

 

I disconected mine at the axle back and it was a good replacement from stock since it was free and all!!! anything to me sounds better then stock....and suprisingly its not loud at all trust me.... but you will have to either fabricate something that will hold your mufflers still or jus take them completely off cuz theyWILL rattle and that WILL bother you

 

I disagree completely about mufflers dont create backpressure. Also disagree zero backpressure is good for an engine.

 

I took mine off for about a month. No problemsor anything, butjust put them back on cuz the rattle from the pipes drive me crazy!!!

 

If you have your mufflers off, install hangers and a clamp to get rid of the rattle. It works, I did it. Also, found pipe extensions at AutoZone and welded it to a chrome exhaust tip from a local exhaust shop.

As for sound, my car is very loud compared to stock or the IMCO exhaust I had on previously. BUT...it's not louder than my boyfriends 76 Chevy Blazer Carb. with Dual Flowmasters [sm=insomnia.gif]

According to my neighbor who is a San Jose Policeman, my car does not exceed the legal decibles.

 

and i have yet to see a car loose power from a not over the top done larger exhasut, i.e a stock 4.6 with a 4" exhaust will be slower