Quiet exhaust system for 454

[blazer2007]

Originally Posted by SCOTI

I have Dynomax brand 'Super Turbos' under my dually.

The system is:
461/OE heads/RV cam
1 3/4" long tube car headers
Dual 3" head pipes w/a 3" 'H' pipe
3" in/out Dynomax turbo mufflers
2.5" tailpipe reducers
2.5" dual tailpipes that angle down/out @ the rear bumper brackets

All tubing after the headers is .065" wall SS. The 3>2.5" transition is immediately after exiting the mufflers which is right @ the back of the cab (CC). It's pretty quiet IMO. The big-block rumble/vibration can still cause car alarms to go off as you pass by if in an apartment complex or a corridor but my dually is 5" off the ground @ ride height

I bought these mufflers based on internet searches using the key words: 'best flowing/quietest mufflers' for my search. I came across multiple muffler comparison tests & reviewed common mufflers from the various tests. My priorities were the best flowing quiet mufflers.

Testing indicated the Super Turbos flowed as good as Borla race mufflers (which were the loudest/2nd to open headers) but were as quiet as OE mufflers (OE were listed as quietest w/the Dynomax as next in line). The testing results that I liked which seemed most informative was from a Pontiac magazine article & was based off of a warmed over 455 equipped wagon that had a 2 into 1 2.5" exhaust arrangement. 'Real world' testing results were on a drag strip which included the track times, sound levels @ cruise rpm & WOT. Since the Dynomax Super Turbos did so well vs. the other more popular brand-X mufflers in the 2.5" version I just got the same mufflers in the largest version I could find (length) in 3" in/out.

Pretty happy with the choice. I plan to get the same ones in 2.5" for my 64 if I don't like the ones it has (I had already acquired them for it before I did my research for the dually set-up).

does it have that loud rapping noise when you step on the gas ? don,t care for that noise like some of the other mufflers