Flowmaster, Magnaflow, Spin Tech

Bud · February 21, 2003

I just talked to Flowmaster. They say that the 530504 is made for the 6.0 and the 8.1. It has dual 3" in and out. It is a 50 series and they say it is "kinda" loud. Has anyone ever used this set up? Is Magnaflow better or quieter? I'm getting old and I don't want loud anymore!!

Anybody ever used Spin Tech?

CMNTMXR81 · February 21, 2003

Never used Spin Tech so I can't comment on that. Although it is a popular choice on F-Body's for a muffler choice on a certain cat-back system (can't remember which right now).

Flowmaster - Never been a fan of Flowmaster unless it's on an old school Big Block Chevy or 5.0 mustang. To me it's got a raspy box of rocks type of sound which isn't exactly my favorite.

Magnaflow - Magnaflow is owned by Walker exhaust systems. Walker also owns DynoMax. As such, Magnaflow's are nothing more than DynoMax's Ultra-Flo polished stainless steel line. Although You can get Magnaflow's in certain sizes you can't get DynoMax for some bizarre reason. DynoMax/Magnaflow have a deep, rumbly, resonance sounding tone. This is what I like. I like to start it up and have the ground shake underneath from the rumble/resonance, and not raspiness and crackling like the Flowmaster's or even a Borla.

With that said, I've had DynoMax systems on my Bravada, Blazer, Tahoe and now Magnaflow on my 2500HD. What does that tell you?

Seriously, listen to what Gandolph and I have for the Magnaflow camp, then find some guys with Flow's, Borla's, SpinTech's, and whatever else and make your own decision. Your hearing will tell you what you like. All will net about the same in terms of performance (+/- HP/torque here and their) so what it boils down to is the auditory experience.

Bud · February 21, 2003

Never used Spin Tech so I can't comment on that. Although it is a popular choice on F-Body's for a muffler choice on a certain cat-back system (can't remember which right now).

Flowmaster - Never been a fan of Flowmaster unless it's on an old school Big Block Chevy or 5.0 mustang. To me it's got a raspy box of rocks type of sound which isn't exactly my favorite.

Magnaflow - Magnaflow is owned by Walker exhaust systems. Walker also owns DynoMax. As such, Magnaflow's are nothing more than DynoMax's Ultra-Flo polished stainless steel line. Although You can get Magnaflow's in certain sizes you can't get DynoMax for some bizarre reason. DynoMax/Magnaflow have a deep, rumbly, resonance sounding tone. This is what I like. I like to start it up and have the ground shake underneath from the rumble/resonance, and not raspiness and crackling like the Flowmaster's or even a Borla.

With that said, I've had DynoMax systems on my Bravada, Blazer, Tahoe and now Magnaflow on my 2500HD. What does that tell you?

Seriously, listen to what Gandolph and I have for the Magnaflow camp, then find some guys with Flow's, Borla's, SpinTech's, and whatever else and make your own decision. Your hearing will tell you what you like. All will net about the same in terms of performance (+/- HP/torque here and their) so what it boils down to is the auditory experience.

Which Magnaflows did you put on your 8.1. I was told by Flowmaster, that ihttp://www.gm-trucks.com/cgi-bin/ib3/ikonboard.cgi?act=Post;CODE=06;f=4;t=16018;p=126619f I put 2 70's on my 8.1 that I would lose low end torque. Have you had any problems?

02 2500 Avalanche · February 22, 2003

Spin tech seems like a great muffler. I have not had the chance to use them but If I get another project I will give them a go. Also CM, the f-body cat back system that uses spin tech mufflers is mufflex.

Alex

gandolphxx · February 22, 2003

I have the 12599 - wanted to try the 6.0L kit, but they refused to deal with me, acted like they didn't know anything about it - sort of sad - in any event the 3" dual in x dual out dropped in like it was made for it - my local guy did a super job on the side out exit - probably saved me a lot over the kit.

As to back pressure, that is a difficult question - I run 7+ psi boost at the track and can do 1.9 60' - don't think I have lost that much with 7000 lbs to push

JimWilson · February 22, 2003

Magnaflow - Magnaflow is owned by Walker exhaust systems. Walker also owns DynoMax. As such, Magnaflow's are nothing more than DynoMax's Ultra-Flo polished stainless steel line. Although You can get Magnaflow's in certain sizes you can't get DynoMax for some bizarre reason. DynoMax/Magnaflow have a deep, rumbly, resonance sounding tone. This is what I like. I like to start it up and have the ground shake underneath from the rumble/resonance, and not raspiness and crackling like the Flowmaster's or even a Borla.

Any resonance in the cab? I like the Magnaflow sound, but don't want an exhaust that drones too.

Bud · February 22, 2003

Spin tech seems like a great muffler. I have not had the chance to use them but If I get another project I will give them a go. Also CM, the f-body cat back system that uses spin tech mufflers is mufflex.

Alex

Anybody know a Spin Tech dealer?

02 2500 Avalanche · February 23, 2003

http://www.spintechmufflers.com/spintech/spintechindex.asp You can buy muffler from SpinTech directly and then just bring them to your local muffler guy and have them welded up. I do not know how much resonance there is going to be in the cab so do not blame me when your wife yells at you

Alex

Shaners · February 23, 2003

I'd really love to add a muffler to my 6.0L. I don't want a cat-back system, but just a muffler (dual in/ dual out).

My two biggest concerns are loss of low RPM torque and resonance. I won't be able to tolerate either of these problems, and I hate to spend the money to hack up my stock stainless exhaust and then wind up totally bummed.

All the graphs I have seen show power boost in the RPM ranges that I rarely see, and the graphs never show what it is like under 3500 RPM...

tps0424 · February 23, 2003

I'd like to add a muffler(s) to my truck too. Towing my camper as much as I do requires that I, at least, maintain the low end torque that I have and, at best, increase it a little.

I'm leaning towards a setup that Tweaker had on his HD and that was the 2.5" dual in/ dual out Magnaflow. He said that he tried a few different mufflers and sizes onhis 6.0 and that's what works best for him. He claimed no loss of low end torque, increased throttle response and a nice sound.

The other option may be to go with dual Flowmaster which Shotgun has. He seems to like them and he says that he hasn't seen any loss of towing power either.

Someday soon, I'm just going to jump in and do it. Until I do, I'm going to keep looking for info on this board and others like it hoping that I can learn from everone else's experience.

CMNTMXR81 · February 24, 2003

Bud, I honestly couldn't tell you what part numbers they were. That was last spring when I did it. As to low end torque loss? None felt here by my highly calibrated butt-O-meter. But even if there was, I can still light them up by just tapping the gas (see the MPG file that the G/F squeels them) and I was out accelerating cars coming out of the tollbooths this past weekend with my 1,500lb MacLander flatbed hooked behind me. If that's a sign of lost torque, sign me up for some more loss!

Mufflex, I knew it started with an "M" but for some reason I just couldn't think of it. Most people I know with the Mufflex though go with the 4" Flowmaster single out though, which is probably why I was at a loss.

And yes Jim, there is PLENTY of resonance in the cab. Enough to give my feet a foot massage from the floors vibrating soo much.

nhkid28 · February 24, 2003

As is says in my signature I have the Flowmaster 40 series. I did not loose any low-end torque when I had it installed. I think that you have to maintain some of the back pressure so not to loose any torque. This is accomplished by the size of the pipe coming from the muffler. For example, my Flowmaster is a 3 in. single inlet dual outlet with 2.5 in. pipes exiting out on either side of my hitch.

As to resonance, Yep I have it. Yes it is loud, but not obnoxiously so. Would I buy it again, yes. I would however change where it exits. I would rather it exits diagonally behind the rear wheels so I don’t get a face full of exhaust fumes while I hook up to my camper.

Bud · February 24, 2003

The more I check into this the more I don't know which way to go! I've only had dealings with Flowmaster and they say the don't have what I need, 50' would be too loud. I'll keep reading you guys keep writing and one of these days I'll just dive in! I would like to find someone that has used the Spin Tech.

Bud

Shaners · February 24, 2003

A friend at work has the 70 series Flowmaster on his 5.3L. It is mellow except when you really get on it. I like the sound of his, but my exhaust has a dual-in/dual-out muffler on it, and I just want to replace the muffler and not the entire exhaust. Two mufflers into the large single tailpipe is a possibillity, but I prefer the idea of the dual-in/dual-out muffler acting as a place for the exhaust to mix from each bank of the engine, as opposed to mixing them in the "Y"-pipe in front of the rear axle.

02 2500 Avalanche · February 25, 2003

Shaners, You could also get a muffler with dual in/single out, that way you could retain all of your stock pipes but just have the new muffler welded in.

Alex