Magnaflow True or False

[Acerone]

In the FAQ's here about increased HP.

http://www.magnaflow.com/07techtips/faq/question22.htm

Question: How much horsepower can I expect to gain?

Answer:
It's different for every car, but typically expected gains are in the average range of 10%.

Replacing the muffler/exhaust with a MagnaFlow will help your engine increase power by being able to expel exhaust gases quicker. This creates less workload for the engine, makes it run more efficient, and results in better power.

 

[Roywhitep5]

magnaflow exhaust adds 20whp

 

[anthony2558]

dont think so...... It may sound like 20 hp though.. I never heard of any exhuast giving 20hp. maybe 2 or 3 hp. Exhuast is really just for the sound and maybe a better free flow, but not 20hp though.

 

[AzMz3]

dont think so...... It may sound like 20 hp though.. I never heard of any exhuast giving 20hp. maybe 2 or 3 hp. Exhuast is really just for the sound and maybe a better free flow, but not 20hp though.

It will one some turbo cars. And I have dyno'd an exhaust to give more than 5hp on a 4 cylinder.
And how do you think they make power, by making it flow better....increasing the size and removing unneccessary bends.
I'd never by an exhaust that was made just for the sound....
Thats is rice right there!

 

[2k3 PrO RiDa]

Whats so rice about buying an exhaust for the tone?They all give you around the same gains anyways...unless you ran no cats or something.To each his own though...

 

[AzMz3]

Whats so rice about buying an exhaust for the tone?They all give you around the same gains anyways...unless you ran no cats or something.To each his own though...

That is not true that all will give you the same gains. I have seen a couple of exhaust shoot-outs that proved that. But if someone making an exhaust for told me that they made it for sound and not to gain HP...Like one did I would quickly mark them off the list.

 

[shibaman]

10% ?

I have had Magnaflow mufflers- not cat backs on 3 different cars. 95 Pathfinder,03 Vibe,and my 04 Mazda 3. I have gotten great results with each. The biggest gain was with the Pathfinder because the oem exhaust was the most restrictive. The least maybe the Mazda 3 ? I think that the oem on this car is not that bad. Only a dyno could tell you for sure. I am too cheap to buy a cat back so I rather replace the cork- oem muffler only. It does the trick also at a smaller cost.
I put a cat back with over sized tubbing on my Jetta and it lost a lot of low end torque-- very bad! You need to keep the tubbing close to oem to keep that torque!

 

[AzMz3]

I have had Magnaflow mufflers- not cat backs on 3 different cars. 95 Pathfinder,03 Vibe,and my 04 Mazda 3. I have gotten great results with each. The biggest gain was with the Pathfinder because the oem exhaust was the most restrictive. The least maybe the Mazda 3 ? I think that the oem on this car is not that bad. Only a dyno could tell you for sure. I am too cheap to buy a cat back so I rather replace the cork- oem muffler only. It does the trick also at a smaller cost.
I put a cat back with over sized tubbing on my Jetta and it lost a lot of low end torque-- very bad! You need to keep the tubbing close to oem to keep that torque!

Keep the tubbing close to the oem? I hope some of the exhaust companies don't think like that! You have r&d with different size diameter exhaust. I'd never just hack off the muffler and replace it, I really doubt that will even get you any gains.

 

[shibaman]

Keep the tubbing close to the oem? I hope some of the exhaust companies don't think like that! You have r&d with different size diameter exhaust. I'd never just hack off the muffler and replace it, I really doubt that will even get you any gains.

If for example your oem is 2" going to a 2.25 or 2.5 will work. If you do 3" it to much for most cars unless they are blown. The most restictive part of your exhaust system is almost always the oem muffler.The cats, also but you can't change those. Not the difference between 2 and 2.5" pipe. Funny how people think that bigger is always better. The other ? is do you want to spend 300$ more for a cat back for a couple of HP? Maybe it is bragging rights? BTW you can feel the difference in performance with only the Magnaflow muffler.
It is the same on CAI. You get better gains on some cars than others. The base Matrix 8hp,5tq, the XRS 12hp,8tq. The Mazda has a better oem intake so there are less % gains.

 

[Protege5 Driver]

If for example your oem is 2" going to a 2.25 or 2.5 will work. If you do 3" it to much for most cars unless they are blown. The most restictive part of your exhaust system is almost always the oem muffler.The cats, also but you can't change those. Not the difference between 2 and 2.5" pipe. Funny how people think that bigger is always better. The other ? is do you want to spend 300$ more for a cat back for a couple of HP? Maybe it is bragging rights? BTW you can feel the difference in performance with only the Magnaflow muffler.
It is the same on CAI. You get better gains on some cars than others. The base Matrix 8hp,5tq, the XRS 12hp,8tq. The Mazda has a better oem intake so there are less % gains.

you guys should see how many people here have no cats oer anything, just stright through exhaust

 

[Da 6]

catback plus heat wrap will give you more of a gain cause hotter gasses are ligher and can be expelled eaisier than cooled of gasses from running too large of a diamiter. also depends on what you wan't low end or high end. the header for 2.3 changes the fingers for a better flow and also sevre as weight savings...if you go tha route I strongly urge you get the coated hearer. As AzMz3 said large diamiter is better for turbo applications. I still don't see 20 HP on just a catback alone...maybe header and light porting i'd be more willing buy into it. For the record my straight thru rear section is for sound only granted it showed how restrictive the stock muflers are just idling alone! I'm already aware my car isn't going to be lightning fast with 1000hp(2.3 MZR) like the world chalenge 6 N/A race car. Moral of the story is if it's a daily driver..I'd pick sound over perfomance any day.

 

[Roywhitep5]

20 whp on a protege5 thats for sure. I no moar than JOOO!!!

 

[mazdaspeedpower]

He's right, on most cars, you do want to keep the piping close to stock sizeing, just because if you go huge, you will lose some much needed back preasure....which is that much loved/needed low end torque. However, if you have a heavly modded engine, getting bigger will work, however, yo never wanna go too big. Yes, removing cats and mufflers do a great job at maintaininga good diameter size, and gaining power. FOr best results on most cars(around 2inch piping), getting 2.5inch with no cats or mufflers will give the best gains(in my experience and research). Thats on a stock, to slightly modded engine...which is what most people here run. Now, once you start getting more modded, like big things giving you larger amounts of power, then it's ok to move up a bit...however, I don't think any of the mazda's here that are N/A need 3in pipes...

 

[Acerone]

OT. mazdaspeedpower,

what are the codes for the scroll in your signature?