Flowmaster Mufflers on Turbocharged Engines.....

[gaugeprower]

Re: Flowmaster Mufflers on Turbocharged Engines.....

Ok so I see the consensus is that the Magnaflow straight through mufflers seem to be the popular and well working option for these trucks due to the turbo system being "choked" by the rattling air that the baffles in a Flowmaster muffler would create. Does anyone have any data/experience showing the comparison of flow and reliability of boost control of the Magnaflow vs the Pitbull and/or Borla? Or could we safely assume those 3 are pretty much all relatively the same? Leaving us to "sound" as a preference of the choice we make between the 3.

Also, has anyone tried to customize a Corsa for these trucks? They also seem to have a baffle type design like a flowmaster...but more like a weird hybrid straight through design as well. Its almost like as if its 90% straight and then the slower moving air (lower RPM) would get pushed into those weird square chambers vs the higher velocity air getting pushed past and out. i'm thinking that would be ok since the turbo is mostly being used at higher RPMs and at WOT which would mean more velocity to that exhaust which would push it past those baffles, and at the lower RPM where we don't use the turbo, we will have the baffles for that sound... Or maybe I'm wrong I dont know... I'm just assuming the airflow is from right to left in the photo I linked to which may not be the case. http://cdn.speednik.com/files/2011/09/IMG_6820.jpg I'm only asking because I love the tighter higher pitched corsa sound even on V6 motors. so if the flow would be comparable to the big 3 mentioned earlier maybe I could get away with one of these too. I love the deep Magnaflow style rumble, but a more "exotic" tone on a SyTy would be something nice and different but only so long as the design wouldnt hinder performance or create a risk of turbo damage

 

[Throws]

Re: Flowmaster Mufflers on Turbocharged Engines.....

Ok so I see the consensus is that the Magnaflow straight through mufflers seem to be the popular and well working option for these trucks due to the turbo system being "choked" by the rattling air that the baffles in a Flowmaster muffler would create. Does anyone have any data/experience showing the comparison of flow and reliability of boost control of the Magnaflow vs the Pitbull and/or Borla? Or could we safely assume those 3 are pretty much all relatively the same?

My experience would lead me to believe that straight through is straight through. There's guys here running no cat/muffler, so it would make sense that a "muffler" of that design would offer only muffling of the noise coming out of the turbo...

:2cents:

-P

 

[gaugeprower]

Re: Flowmaster Mufflers on Turbocharged Engines.....

I was thinking that too so now I don't feel too bad about the Pitbull, since it's one of the straight through types. I just had a bad experience with anything branded ATR so I just had a preconception that it was garbage just like everything else ATR made that ended up on my truck. Now it just leaves me the matter of choosing (eventually) deciding between the PB or the Corsa, obviously the straight through will have the better flow, but if there isn't much noticeable difference, it would add another (unexpected) sound option.

 

[Darin]

Re: Flowmaster Mufflers on Turbocharged Engines.....

For what it's worth:

Back to back comparisons on my last Talon (FP 3052 turbo, 85lb inj, FMIC, DSMLinkV3, forged internals, HKS272's, blah blah blah):

2.5" downpipe, stock catback: 13.2
3.0" turbo back exhaust (Thermal R&D catback and a homemade 3" downpipe, no cat): 12.3
6" stub of 3" off turbo pointing down: 11.9

First run was at 18psi or so, it wouldn't make any more than that. Last 2 runs were at 22psi. You can see the dramatic increase that a free-er flowing exhaust makes. Yes, I realize that a lot of the extra power gained was from the extra pressure, but that just proves my point even moreso.

Granted, these runs were with a Gtech, but done on the same day, very similar conditions. The improvement over the stock exhaust was phenomenal.

My advice on exhaust when asked: Go as free flowing as your ears. neighbors and the boys in blue will allow.

My Typhoon currently has a Borla cat back and stock everything else. I will be switching to a 3" downpipe and electric cutout soon, however. Best of both worlds!

 

[midnightbluS10]

Re: Flowmaster Mufflers on Turbocharged Engines.....

Ok so I see the consensus is that the Magnaflow straight through mufflers seem to be the popular and well working option for these trucks due to the turbo system being "choked" by the rattling air that the baffles in a Flowmaster muffler would create. Does anyone have any data/experience showing the comparison of flow and reliability of boost control of the Magnaflow vs the Pitbull and/or Borla? Or could we safely assume those 3 are pretty much all relatively the same? Leaving us to "sound" as a preference of the choice we make between the 3.

Also, has anyone tried to customize a Corsa for these trucks? They also seem to have a baffle type design like a flowmaster...but more like a weird hybrid straight through design as well. Its almost like as if its 90% straight and then the slower moving air (lower RPM) would get pushed into those weird square chambers vs the higher velocity air getting pushed past and out. i'm thinking that would be ok since the turbo is mostly being used at higher RPMs and at WOT which would mean more velocity to that exhaust which would push it past those baffles, and at the lower RPM where we don't use the turbo, we will have the baffles for that sound... Or maybe I'm wrong I dont know... I'm just assuming the airflow is from right to left in the photo I linked to which may not be the case. http://cdn.speednik.com/files/2011/09/IMG_6820.jpg I'm only asking because I love the tighter higher pitched corsa sound even on V6 motors. so if the flow would be comparable to the big 3 mentioned earlier maybe I could get away with one of these too. I love the deep Magnaflow style rumble, but a more "exotic" tone on a SyTy would be something nice and different but only so long as the design wouldnt hinder performance or create a risk of turbo damage

That's their RSC design, I believe. Reflective sound cancellation. They're looking to cancel certain frequency sound waves to take out some of the interior resonance and drone. It's a straight through design, also.

http://www.corsaperformance.com/technology.aspx

 

[gaugeprower]

Re: Flowmaster Mufflers on Turbocharged Engines.....

Hmm, this is starting to look promising... as long as the 4.3 doesn't sound as ricey as the 3.6 in the 2010 Camaro (of which im sire the 4.3 sounds deeper) This could be a nice option... now to get my hands on that muffler :squint: I'm not all about buying a 1,000 complete dual exhaust system if all I really need is just that one muffler to replace the pitbull one...

 

[Throws]

Re: Flowmaster Mufflers on Turbocharged Engines.....

Hmm, this is starting to look promising... as long as the 4.3 doesn't sound as ricey as the 3.6 in the 2010 Camaro (of which im sire the 4.3 sounds deeper) This could be a nice option... now to get my hands on that muffler :squint: I'm not all about buying a 1,000 complete dual exhaust system if all I really need is just that one muffler to replace the pitbull one...

Magnaflow# 12619 ( I think this is what I'm running). Just match a Magnaflow 6" round to the body length you currently have. :tup:

-P

 

[gaugeprower]

Re: Flowmaster Mufflers on Turbocharged Engines.....

Nice, that's perfect for magnaflow, now to find a part number if I decide on Corsa. I know that 14953 is the whole system "sound-tuned" to a 3.6 V6 Camaro (closest tune i could find since most of their applications are for v8's) They dont have a 4.3 application but all I would need is just one of those mufflers. The rest of the pipe is all straight through idk if the cat was deleted or not I think the exhaust the previous owner installed was an atr "turboback" If it turns out to be too much of a pain in the ass to go Corsa, I'll definately pick that magnaflow up since its only around 80-90 bucks. Thanks again for that PN :tup:

 

[midnightbluS10]

Re: Flowmaster Mufflers on Turbocharged Engines.....

Nice, that's perfect for magnaflow, now to find a part number if I decide on Corsa. I know that 14953 is the whole system "sound-tuned" to a 3.6 V6 Camaro (closest tune i could find since most of their applications are for v8's) They dont have a 4.3 application but all I would need is just one of those mufflers. The rest of the pipe is all straight through idk if the cat was deleted or not I think the exhaust the previous owner installed was an atr "turboback" If it turns out to be too much of a pain in the ass to go Corsa, I'll definately pick that magnaflow up since its only around 80-90 bucks. Thanks again for that PN :tup:

Good luck finding a single Corsa muffler. It seems they don't sell just mufflers :dunno:

 

[Davemc1963]

Re: Flowmaster Mufflers on Turbocharged Engines.....

I've a few rambling thoughts (all mine and unsubstatiated as I've never had any experience of a Flowmaster other than hearing one. If they come across as authoritative they're not, I'm not an authority on any of it, they're just my thoughts out loud to add to and promote thread discussion). As has been mentioned by others, my thoughts were that the flowmaster relies on the pulsewaves to 'function' in respect of sound control using sound wave reflection to cancel out different exhaust sound frequencies together with expansion of the gasses in the various chambers to achieve what it does with regard to the deep but 'slightly muffled' sound it produces, taking out the pop and bang you get without a muffler on a n/a or supercharged motor. I dont see how a F/M would perform better than a straight through on a turbo motor due to the fact it can't flow as well by design. A straight through muffler relies mostly on absorbtion to quiet the exhaust which I expect does have some effect on flow albeit a minor one. In a turbo motor again my view and repeating what some others have referred to, unlike the exhaust in a n/a or supercharged motor the exhaust after the turbo has lost an awful lot of its energy by powering the turbine/compressor and doesn't have the same cylinder pulses you can feel on a non turbo. Much like a steam turbine does in principle, the exhaust after the turbine needs to be evacuated as efficiently as possible to reduce backpressure and allow more throughput. As mentioned in the link that Quickstop posted if you could suck the exhaust out with a vacuum cleaner that would be even better.
It makes me think whether you could rig up an air extraction system that uses air velocity from the vehicle to create a vacuum and suck the exhaust out, I assume to do this you would need a considerable velocity of air to achive this. Anythings possible but the returns probably wouldn't justify the trouble, but who knows? If you dump at the downpipe it all becomes academic, thats sorta deviating too much though. Bottom line while I like some Flowmaster sounds, I dont think the principles they utilise can benefit a turbo motor over a straight through unless you want that sound and that is what its all about sometimes isn't it? End of ramble.

 

[jaystcb]

Re: Flowmaster Mufflers on Turbocharged Engines.....

if you could suck the exhaust out with a vacuum cleaner that would be even better.

I could be wrong but.... I beleave that some Corvette mufflers have a vacuum solenoid that under full throttle it opens another exhaust port on the muffler for more exhaust flow and HP.

Can we use this technology on our trucks using a 2nd muffler or a dump pipe to increase HP?

Thank you Dave for starting this thread.

 

[warmpancakes]

Re: Flowmaster Mufflers on Turbocharged Engines.....

I could be wrong but.... I beleave that some Corvette mufflers have a vacuum solenoid that under full throttle it opens another exhaust port on the muffler for more exhaust flow and HP.

Can we use this technology on our trucks using a 2nd muffler or a dump pipe to increase HP?

Thank you Dave for starting this thread.

electric dump hooked to a XXX Psi hobbs switch

 

[Darin]

Re: Flowmaster Mufflers on Turbocharged Engines.....

ATP turbo used to sell a vacuum/boost pressure exhaust dump using a diaphragm style actuator and a butterfly valve.

This is, however, getting away from the original topic.

 

[alwayscode390]

Re: Flowmaster Mufflers on Turbocharged Engines.....

Good luck finding a single Corsa muffler. It seems they don't sell just mufflers :dunno:

This is true. I just had a guy try to sell me a used muffler for $250 shipped to replace the broken resonator on my ZR-1 ... no thanks ... I'll be going x-pipe instead lol ---

 

[Damian]

Re: Flowmaster Mufflers on Turbocharged Engines.....

There are a couple Corsa mufflers on eBay. Corsa exhausts do sound great.

 

[alwayscode390]

Re: Flowmaster Mufflers on Turbocharged Engines.....

There are a couple Corsa mufflers on eBay. Corsa exhausts do sound great.

4" for $275 shipped ... wow. Not sure what they sound like on our trucks, but they sound great on the Viper!!! No drone at ALL ... the Borlas on my ZR-1 drone like a mofo.

FLOWMASTER 3" soundclip on a Syclone :

http://www.youtube.com/watch?v=m69432q5alE ---

 

[gaugeprower]

Re: Flowmaster Mufflers on Turbocharged Engines.....

So it's looking like the only way to pick up a corsa would be to find a discontinued "Corsa DB Red or DB Black" series muffler. These were produced for a little while and seem to have been popular with the GTO, Stang, and G8 guys. I havent heard one on any type of v6 motor. The red series was apparently the quieter of the two. I've don a little research and its all coming up empty, which is good and bad. Since I cant find any for sale, that means everyone who bought one freaking loves it and wont sell it. But its also bad because, well how the hell am I supposed to get one then? haha

 

[Damian]

Re: Flowmaster Mufflers on Turbocharged Engines.....

Awhile back, both those mufflers were on eBay. Maybe I should have picked one up when I bought my Dynomax.

Someone try the Corsa 4"! I'm thinking of changing out the catback with a 4" anyways.

 

[Quickstop [UK]]

Re: Flowmaster Mufflers on Turbocharged Engines.....

There has been a dearth of technical content on the forum lately. This is an attempt to jump-start some participation in technical subjects by knowledgeable people again.

Over the years I've seen posts here stating: "Flowmaster mufflers are not good on turbo engines" time and again. I saw this again this morning in another thread. OK, fine. Why not?

I found this article by David Vizard. Evidently Mr. Vizard was responsible for developing the concept muffler that became the Walker Super Turbo that was on SyTy as OEM equipment. This article was written regarding exhaust on N/A racing engines with tubular, collected, exhaust systems.

I gleaned from the above article that the Flowmaster muffler 'appears' to the the pulses as the end of a round pipe, such as a header collector and there fore can be used to "tune" collector length for torque. I understand this. A turbo smooths out the pulses. Turbo engines are sensitive to back pressure downstream the turbine. A straight-through design is favored. The DynoMax is not a straight-through muffler, but is acceptable? Comparing the designs of Flowmasters and DynoMax seems to me that the Flowmaster is freer flowing than the Dynomax. What am I missing?

I spent about an hour looking for a direct "Flowmasters cause power-loss when installed on a turbocharged engine" but never found anything online. Can anyone point me to a definitive explanation supporting this statement, rather than it just being "something I read on the internet?"

Thanks, and Merry Christmas

Probably doesn't help when people delete useful technical info...

For posterity.