NBred94

I just ordered a Magnaflow #14589 5inch x 11 oval muffler center inlet/offset outlet. I'll get the local shop to weld it up and replace that ungodly monstrosity of a stocker. I ran across a few threads that mentioned this one to be a good replacement for the stocker if all you want to change is the muffler.

The body on the stocker is about 25" long, and this one is 28" in total length, so I'm hoping it will weld up with minimal fuss.

It will be nice to hear a V-8 sing again. I've been missing that sound since I sold my Z28 (which also had a Magnaflow).

blake2kz71

iTrader: (17)

a little advice.......If i had it to do over again, i would have bought a catback system even though its more money, its worth it. (mandrel bends, truck specific, no cutting or welding) also if you get the pacesetter lt's it will bolt right up to a catback system. I could kick my *** for not going with a catback system, but then again just some words of advice.

NBred94

Well, since I am unlikely to ever do anything beyond bolt-ons, I feel pretty confident that the stock tailpipe will not be too restrictive. I will always run cats on my truck, so any significant gain that I am going to get from freeing up my exhaust will be in the muffler itself. For me, it comes down to having the shop down the street cut and weld for $50 rather than drop an additional $400 on the catback piping for maybe another 2 or 3 hp. For the difference in price, I can go get a top notch dyno tune.

If you are ditching the cats, maybe its worth it, but I don't want to have to go through the trouble of having to go around emissions every year, so I'll probably just stick with the manifolds and cats. Downstream from that restriction, I don't think that the extra 1/4" of pipe diameter would make that much of a difference. If I somehow manage to get a set of dynatechs someday, I may reconsider.

8MC

iTrader: (3)

Good call. That's the same muffler I ended up with on mine. Only difference in set-ups is that I went to 3" tubing with it dumped after the axle. Don't expect it to scream, but it does add a nice V8 tone.

Mr. Sandog

If I had it to do all over again I would have NOT gone cat-back and gone muffler only with the Avalanche. Actually, I did have to do it over again....and ended up getting a couple of Magnaflow mufflers that worked out awesome.

NBred94

I think I remember seeing your setup back when you were NakedAV.

If this ends up being too loud (which apparently it won't) I had contemplated putting a bullet muffler in line with it.

NBred94

That's exactly what I want. No harsh loudness or drone, but a good deep rumble when I get on it .

Mr. Sandog

That's the great thing about designing your own system and not going with a catback...you can modify and modulate the sound as you like. Install the smallest muffler you think you can handle, and if it's too loud, put another one in line with it. Pretty simple actually, and puts you in control of the outcome, rather than a shop or manufacturer.

marooned

I installed that muffler on my Z71 and only added 6" of 3" pipe to make it work.It gives it a nice tone and feels like it improved driveablity but the drone in my cab at 1600 RPM is not very pleasant.I'm looking for solutions?

Mr. Sandog

Install another, smaller Magnaflow either before or after the main muffler. They make some 11" mufflers that would do the trick quite handily.