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Bye Bye Lm Hello Magnaflow

Old Oct 17, 2006 | 05:38 PM
  #21  
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Love my magnaflow. No rust either then again I dont take it out in the rain/salt/snow.
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Old Oct 17, 2006 | 05:40 PM
  #22  
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i make over 720rwhp with a magnaflow, untuned baseline, and plan on making over 800 quite easily
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Old Oct 17, 2006 | 05:42 PM
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Originally Posted by 300bhp/ton
LM is 3" and while the Magnaflow is good it's proven to be a restriction on cammed, h/c setups. It will NOT flow as well as the LM. Just take a look at the mufflers, LM = straight thru, Magnalfow = not.
Wrong, the Magnaflow is a straight thru design. Take one and hold it up to your eye, you can see right through it. Why did you get 1 7/8" Kooks? They are too big for a car without a power adder. You are loosing some bottom end hp and torque.

Last edited by SOMSS; Oct 17, 2006 at 05:48 PM.
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Old Oct 17, 2006 | 06:35 PM
  #24  
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Originally Posted by Justin00SS
It makes and S design.

Its on their website.
Could you help me find that?
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Old Oct 17, 2006 | 07:05 PM
  #25  
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Originally Posted by TAQuickness
Could you help me find that?
It was there. Hang on.
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Old Oct 18, 2006 | 04:08 AM
  #26  
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Originally Posted by SOMSS
Wrong, the Magnaflow is a straight thru design. Take one and hold it up to your eye, you can see right through it.
Yeah like I have one sitting on the floor next to me.

BTW - ,aybe it is straight thru then, do you have a cut-away picture of one at all? But due to the dual exit and non linier flow this will produce I very much doubt it will flow as well as a LM resonator.

EDIT:

Originally Posted by SOMSS
Why did you get 1 7/8" Kooks?
I'm gonna assume this wasn't aimed at me, as I don't have those headers.

Originally Posted by SOMSS
They are too big for a car without a power adder. You are loosing some bottom end hp and torque.
Although I do disagree with this.
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Old Oct 18, 2006 | 05:50 AM
  #27  
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I havent seen too many people bash Magnaflow. I have flowmaster and have good reason to bash them. I have the stainless cutout and when I dynoed back to back, the flow is costing me 32rwhp under the cutout open. Anyway, I was wanting to go to Magnaflow or maybe B&B. I love the look and the fact that its stainless. But Magnaflow for the price. I will give the flowmaster volume. Its friggin loud with LT's, ORY and MS4
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Old Oct 18, 2006 | 06:38 AM
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I'm not bashing the Magnaflow, just stating that I personally doubt it flows as well as the SLP LM.

EDIT:

Take a look at this thread: https://ls1tech.com/forums/dynamometer-results-comparisons/522896-my-99-z-mustang-dyno.html

It's a dyno run of a pretty stock Fbody, exhaust, lid p&p TB. Yet they still picked up 5rwhp over the Magnaflow catback with the cutout open. So it proves the Maganaflow is a slight restriction even at this level. The restriction will increase with the more HP produced. By how much I really don't know.

It should also be accepted that the cutout may have also affected the exhaust pressure wave.

Last edited by 300bhp/ton; Oct 18, 2006 at 06:45 AM.
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Old Oct 18, 2006 | 09:07 AM
  #29  
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i had LM on my 2000 z and i got magnaflow on my 2002 right now. as of right now, i would probably take the LM since im stock manifolds and since it is louder. but i know im going with headers and ory so thats why i took magnaflow this time. first i just had an slp lid. then i installed the magnaflow, and as far as the sotp feel, it woke up my car. it felt torquier as hell too.. cant wait to do headers. but yeah, the magnaflow is quiet.
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Old Oct 18, 2006 | 03:09 PM
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Originally Posted by 300bhp/ton
Yeah like I have one sitting on the floor next to me.

BTW - ,aybe it is straight thru then, do you have a cut-away picture of one at all? But due to the dual exit and non linier flow this will produce I very much doubt it will flow as well as a LM resonator.

EDIT:
That's the catback for a V6. The one for the LS1 has the passenger side outlet right next to the inlet with no restriction. That's why the passenger side tip is louder than the drivers side tip. As for the 5 hp issue. Any amount of exhaust is going to be more restrictive than a cutout. You'd see a gain over the loudmouth also. I'm guessing the Loudmouth and Magnaflow are pretty close.
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Old Oct 18, 2006 | 03:18 PM
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Originally Posted by 300bhp/ton
I'm not bashing the Magnaflow, just stating that I personally doubt it flows as well as the SLP LM.

EDIT:

Take a look at this thread: https://ls1tech.com/forums/showthread.php?t=522896

It's a dyno run of a pretty stock Fbody, exhaust, lid p&p TB. Yet they still picked up 5rwhp over the Magnaflow catback with the cutout open. So it proves the Maganaflow is a slight restriction even at this level. The restriction will increase with the more HP produced. By how much I really don't know.

It should also be accepted that the cutout may have also affected the exhaust pressure wave.
I agree. The more power you have, the more power difference there will be betwen cutout open and through the exhaust.
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Old Oct 19, 2006 | 04:33 AM
  #32  
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Originally Posted by Dal1as
That's the catback for a V6.
my bad, although according to Magnaflows website this one is for a LT1.

Here's the LS1 version:


Originally Posted by Dal1as
The one for the LS1 has the passenger side outlet right next to the inlet with no restriction.
So the exhust gases would be required to do a 180 degree turn, doesn't sound straight thru or opitmal to me.

Besides how does that make it any more "straight--thru"???? The pic of the LT1 version still has a side outlet next to the inlet, it just happens to be on the opporsit side of the muffler.

Originally Posted by Dal1as
As for the 5 hp issue. Any amount of exhaust is going to be more restrictive than a cutout.
Not according to David Vizard, try the sticky (exhaust/induction) there's a link in my sig to it, and read post 13 onwards.

Originally Posted by Dal1as
You'd see a gain over the loudmouth also.
I honestly don't know, the LM resonator may produce some turbulance and I'm not sure it's affect on the exhaust pressure wave, but these attributes affect the Magnaflow. But the LM is striaght thru, no turns no restriction. I feel confident in saying that the LM resonator actually flows better than the 3" tubing either side of it. So a cutout would yield no gain in flow and thus no HP for that reason. Any gain would more likely be attributed to the affect on the exhaust pressure wave.

Originally Posted by Dal1as
I'm guessing the Loudmouth and Magnaflow are pretty close.
Possibly, but the more HP you have the bigger the descrepancy is likely to become.
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Old Oct 19, 2006 | 06:39 AM
  #33  
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I have the lm1 and took out the resanator and put in a mangnaflow bullet and it sounds great compared to the resnator that was on there. Alot deeper nad killed almost all the rasp
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Old Oct 19, 2006 | 08:23 AM
  #34  
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Originally Posted by 2001z
I have the lm1 and took out the resanator and put in a mangnaflow bullet and it sounds great compared to the resnator that was on there. Alot deeper nad killed almost all the rasp
That would be the "magnamouth".
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Old Oct 19, 2006 | 02:47 PM
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Originally Posted by 300bhp/ton
my bad, although according to Magnaflows website this one is for a LT1.

Here's the LS1 version:
I believe The LS1 version and LT1 version are the same and the pictures are messed up. There was a post a few months a go about that and I think and LT1 guy confirmed it. It was about the exhaust being much quieter on the LT1 Magnaflow and not the LS1 Magnaflow or something to that effect. Doesn't pertain to this subject though.

Originally Posted by 300bhp/ton
So the exhust gases would be required to do a 180 degree turn, doesn't sound straight thru or opitmal to me.
Not optimal but not as bad as it sounds. If you look inside the Magnaflow muffler you'll see the inlet goes straight through the drivers side and the muffler itself is pretty empty with a lot of space. Turbulence may be an issue but being this far downstream where the exhaust has already split the flow I doubt it's much of a restriction. Definately not optimal but not really restrictive.

Originally Posted by 300bhp/ton
Besides how does that make it any more "straight--thru"???? The pic of the LT1 version still has a side outlet next to the inlet, it just happens to be on the opporsit side of the muffler.
Look at the picture again. The LT1 or V6 version or whichever it is has the inlet on the passenger side and both outlets on the drivers side with the passenger side tip taking a full wraparound. Exhaust is about scavanging and flow. A longer path is more restrictive.


Originally Posted by 300bhp/ton
Not according to David Vizard, try the sticky (exhaust/induction) there's a link in my sig to it, and read post 13 onwards.
True, it depends on how powerfull the car is. When they start getting up to the higher horsepower numbers is when even the better flowing exhaust setups start being restrictive.

Originally Posted by 300bhp/ton
I honestly don't know, the LM resonator may produce some turbulance and I'm not sure it's affect on the exhaust pressure wave, but these attributes affect the Magnaflow. But the LM is striaght thru, no turns no restriction. I feel confident in saying that the LM resonator actually flows better than the 3" tubing either side of it. So a cutout would yield no gain in flow and thus no HP for that reason. Any gain would more likely be attributed to the affect on the exhaust pressure wave.
I still say a cutout would yield better results than the loudmouth on high horsepower setups. I know we've done back to back dynos with Magnaflow and cutout and showed about a 5 hp difference. It was a 400 horsepower car. I'm guessing the loudmouth on the same car would yield a bit better results but still eat a couple horsepower.

Like I said the loudmouth should be less restrictive seeing as it uses just a resonator but the Magnaflow setup has been tested and flows great. Both exhausts would starte eating power on the higher horsepower setups though.


Possibly, but the more HP you have the bigger the descrepancy is likely to become.[/QUOTE]
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Old Oct 19, 2006 | 05:41 PM
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I might be a dumb-***, but gaining only 5hp with a cut-out, tells me that the Magnaflow is flowing pretty damn well...
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Old Oct 19, 2006 | 10:31 PM
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Originally Posted by 02SS#406
I might be a dumb-***, but gaining only 5hp with a cut-out, tells me that the Magnaflow is flowing pretty damn well...
There is only so much hp to gain with exhaust anyway. Especially with how well most of the headers scavenge.

25-30rwhp on a mostly stock car with exhaust mods is pretty much it.
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Old Oct 19, 2006 | 11:24 PM
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The second one he posted is the right picture for the V8, I just got it last week and thats exactly what came in the box
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