Flowmaster 70 Series aka "Big Block II" Muffler

[Stroppe-Envy-77]

Anyone run one of these in a 2-into-1 system? Looking for something with just a little more of a note than stock, but not overly loud, especially at a steady cruise.

Flowmaster web site lists it as having "mild sound" whereas their other choices are called "moderate sound" (50 Series, 60 Series, Hushpower) or "aggressive sound" (40 Series, Super 44). They also have a video clip of a late-model Suburban with a 70 Series driving past the camera, but it's hard to get a good idea from that.

Also, for those of you who own or have owned various years of Broncos, how much of a quieting effect does the catalytic converter provide? I'm thinking it must have at least a little quieting factor, to where a Bronco with a cat would be slightly quieter than one with the same muffler and no cat.

Thanks!

 

[BurntOrange74]

i run a two into one and have a flowmaster delta flow 40 series (center in/center out), 2.5 inch pipe. sounds good, deep growl but not too loud. i had the two into one magnaflow (center in/center out) but did not like it. seemed like at higher speeds it was too much noise, like a drone noise. my only other thought would be to try the flowmaster hushpower. im not sure if it has the classic flowmaster sound, but if it does i would probably like it. esp since it would give you good clearance all way round.

Just my .02

 

[Broncobowsher]

Something like this?

 

[Stroppe-Envy-77]

Something like this?

No, more like replace the stock-type round muffler that sits behind the single cat with something a little more interesting.

The Flowmaster 70 is a big 'un, with a body that's 22" long. I'll keep the pipe exiting behind the rear tire.

 

[Crawdad]

Here is an install thread I did a few months ago. Along with new headers I bought BCs pipes but not the 2-in 1-out muffler. I wanted something quiet for hunting so I "tried" to buy the biggest and quietest muffler Magna Flo had that would fit my application. Besides I got this muffler from Advance Auto with a 20% coupon and free shipping, very hard to pass that up! I was able to crank my bronco the other day (a loooooong story) and it sounds good in park. I have not been able to run the pipes out the back so there is a lot of noise in the cab at this moment. When I get the leaking carb (needles sticking) I hope to hear it on the road soon. The muffler sits inside & about an inch below the frame which is not too bad. As you will see I did the 2-in 2-out. Here it is:

http://carolinabroncos.com/forums/showthread.php?t=3690

 

[76Bronco302]

I wanted the same thing with my f150. No drone but a deep low tone. Went with the super 44 dual in/dual out dumped over the axle. It sounded great.