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Magnaflow's

R

Rescue_1

Charter Member
Full Member
Joined
Mar 17, 2002
Messages
355
Location
Delaware
Anybody around the east coast(mid atlantic) running magnaflo's? I am going to change my exhaust and I have a guy who does my exhuast work, he is listed as a magnaflo dealer. I am curious to hear what it sounds like on a AV.

Second question is did you change just the muffler or run two pipes after the muffler? I am still thinking about the magnaflo with two outlets, but don't want to loose the torque from the lack of backpressure. My last three trucks have had dual pipes either from the convertor to two mufflers or two pipes from the muffler.

I like the looks of the Corsa exhuast tip, maybe I can get something similar. Just curious to see if I should make two pipes come to the side or one that y's in to the two tips. ? ?
 
I had a magnaflow cat back system on my 2001 Suburbam ,and I traded the Sub for my Avalanche. I kept the magnaflow exhaust and put it on the avalanche. A direct bolt on. The exhaust is awesome in my opinion, its not really loud during normal driving but it comes to life when you get into it. I love it. Very nice stainless steel. You could hang the muffler on the wall and use it as a mirror if you wanted. Improved my milage by 2 MPG also. Easy to put on also. The hardest thing is , is to take yours off. Jack the truck up take the right rear shock bolt out (so the axle is hanging in the air and unbolt the stock exhaust slide it to the rear and drop it down. Oh you have to drop the spare tire also. takes about an hour or so. Did for me anyway. Good Luck Deciding.
 
Forgot to tell you The exhaust I have is a single pipe that bolts directly to your factory one no cutting or anything. One muffler and single tail pipe 4in in diameter all stainless steel.
 
Thanks for the input. You aren't near the east coast are you? Would really like to hear one...
 
Hey Rescue, If you want that really throaty sound at idle and above, then go with a 2 chamber Flowmaster. It does resonate a low hum in the cab when your cruising though. I had one on my Av for 3 months. From outside the truck you can't beat the sound. Pure Chevy V8. I just pulled it off because I got tired of the noise inside the truck on long freeway drives.

I changed over to Magnaflow which is unlike the Flowmaster has insulation to absorb the sound making a much quieter ride. The Magnaflow comes alive when you step on it. It is a mellower sound.

The Magnaflow Purrs
The Flowmaster Growls

No difference in fuel economy or performance gains between them

Just my 2 cents


Len
 
I've never tried or heard the Magnaflow so I can't say anything for a comparison, but has anybody tried stepping down from a 40 series to a 50 or 70 series. ?The 70's are made for the newer trucks and seem a lot quieter.

Flowmaster Products

>:D :B:


G-xx:url
 
I originally had a magnaflow exhaust installed with dual exhaust-had it for about 2 weeks. Liked the sound during city driving, however could not get used to the noise at highway speeds. Went on a 500 mile trip (18MPG @70-75mph) and the noise was unbearable. Swithched over to the Flowmaster 70 series. Sounds nice in city driving, quieter than magnaflow. Big difference in highway driving-not noticeable up to 60-65mph, above that a little more noticeable than stock.
 
I had my muffler guy order a replacement magnaflow for me today. I am going to just replace the muffler instead of doing a cat back system. Since the AV already has a 3" system, it would not be worth the money for me to do it. I am paying $82 for the muffler as opposed to $480 for the cat back system. The 4" tip isn't worth that much money sorry...



 
I have just put the smaller (noisier) Magnaflow stainless (muffler only) on and outside the vehicle it sounds great. Quiet at idle and cruise (mostly) and deep when you stuff your foot to the floorboards. However, under partial or light loads, between 1600 and 2000 rpm there is a substantial in cab resonance. If you were accelerating slowly or going up a slight grade you hear it loudly droning away. With my 3.73 gears it occurs between 65 to 75 mph. I drive a many long days to go fishing ( Seattle to Missoula, 7 hours non-stop ) and I am afraid that it will drive me nuts. I am going to the muffler shop tomorrow to see if the larger (quieter) muffler would cure this. I hate giving up the great tone of the muffler. I suppose I could turn the radio way up!
 
Well, I went and changed to the larger, quieter Magnaflow to lessen the resonance I was getting between 1600-2000 rpm. The droning has lessened, but so has the wonderful exhaust note. It is not anemic like the stock muffler was but lacks the authority of its louder sibling. I am told by the shop that flow is still very good, its just quieter due to the larger size. I guess you cant' have everything!
 
I just installed the Larger Magnaflow's (5x11x22) and am a little disappointed in the quality and volume of the exhaust. Does anyone have the medium mufflers installed?? If so, can you still hear the passengers or the radio?? (Maybe this wouldn't be a bad thing as my wife reminds me that I am spending too much time and $$ on upgrades) Can anyone give me a comparison vs one of the Flowmasters? Just wanted to get the consensus before I have the shop make the switch. Thx!
 
Smelch, I thought that the larger Magnaflows sounded a bit limp, but if you do any travelling the resonance that occurs at 1800 with the louder one will drive you nuts. People that have heard my truck as I drive by accelerating say it sounds great.YMMV.
 
I just measured the center-to-center spacing on the factory piping in and out of the factory muffler. The spacing on the two inlet pipes is 4-1/2 inches, and the spacing on the outlet pipes is 5-1/2 inches.

Magnaflow's 5x8 dual in/dual out has 4" c/c spacing on both the inlets and outlets. Magnaflow's 5x11 has 5-3/4" c/c spacing. I do not want to go with the larger muffler, beacuse it might not provide me with the sound I want. But will the 5x8 work? I am concerned that the muffler shop will not be able to "compress" the wye just downstream of the muffler so it can mate up to the 4" c/c on the 5x8 muffler.

What are ya'lls thoughts...I need to spend some money. I need a pick-me-up. Have had a terrible week.
 
:rolleyes: Installed, on Monday, a series 40 Flowmaster, which is what I was running on my 2000 GMC. I just replaced the stock muffler with the Flowmaster, keeping everything else the same.

Although I haven't tried the other brands (am pretty loyal to Flowmaster) I sure do love the sound of my Flowmaster.

Definately GROWLS >:D >:D >:D >:D :B:
 
I had the 40 series Flowmaster on my Av for a couple of weeks. Very potent sound. Very high in cab resonance at 2000 rpm. (cruise) The 50 series still sounds the same but quieter inside at cruise. The 70 series is much tamer outside and has no resonance inside.

I pulled off the 70 series yesterday and am trying the 50 series for a while.
 
XRover said:
I had the 40 series Flowmaster on my Av for a couple of weeks. Very potent sound. Very high in cab resonance at 2000 rpm. (cruise) The 50 series still sounds the same but quieter inside at cruise. The 70 series is much tamer outside and has no resonance inside.

I pulled off the 70 series yesterday and am trying the 50 series for a while.
Click to expand...

I am glad your living up to your avatar ;D

I am really curious as to how quiet the 50 is inside, I really want to kill that resonance @ 1800 RPM - thanks ;D
 
XRover said:
I had the 40 series Flowmaster on my Av for a couple of weeks. Very potent sound. Very high in cab resonance at 2000 rpm. (cruise) The 50 series still sounds the same but quieter inside at cruise. The 70 series is much tamer outside and has no resonance inside.

I pulled off the 70 series yesterday and am trying the 50 series for a while.
Click to expand...
X, are you using a cat-back system where the mufflers clamp on, or are you getting the mufflers welded on the factory piping?
 
I've never had any experience with the magnaflow systems, but now that I have my flowmaster I don't know if I would ever consider switching to anything else....I like it tremendously... :B:
 
I put on a flowmaster 40 series with the two exits running straight out the back. Definitely a good growl when accelerating, and very noticeable even on the inside. Not for those looking to stay somewhat quiet.
 
Do you guys have part numbers for the Flowmasters you are using??

Are you using the single, center in, with the dual out's? What size inlet and outlets?

:)

Thanks!
 
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