Mazda 6 Forums banner

1 - 13 of 13 Posts

·
Registered
Joined
·
206 Posts
Discussion Starter #1
Hey everyone, Im looking to replace my exhaust from the manifold back for the little extra sound and performance. Im looking for something nice and throaty, but not overbearing. I was thinking maybe you guys could give me some suggestions of different set ups, or maybe that yours works for you, before i go and spend the dough. Thanks for the input all!!
 

·
Premium Member
Joined
·
5,156 Posts
Check out the numerous stickies and threads. Bottom line, Injen cat back is the most expensive but no longer made. Magnaflow's give the best bang for the buck, axle-backs like racing beat are also good too, but for the cash might as well go Magnaflow. BUT.... if you want, go to your local muffler shop, talk to them and discuss what you want and they can custom make something for you for fraction of the cost of exhaust system prefabbed.

GL
 

·
Registered
Joined
·
3,228 Posts
QUOTE (Awong124 @ Jan 21 2010, 12:17 AM) index.php?act=findpost&pid=1631203
Here's a video of the Injen catback:

http://www.youtube.com/watch?v=gp5txIhi1bY


Here's a video of the Injen catback with NPG Racing headers:

http://www.youtube.com/watch?v=XNJc-Z0Cke0[/b]
Any power gain difference between the NPG and the cp-e headers? How was the install on the NPG, any modifications you have to make to get them to fit, how about CELs? Sounds nicely matched with the Injens. Try playing both of your videos at the same time but side by side, you get a great comparison of sound.
 

·
Registered
Joined
·
2,854 Posts
QUOTE (HighSpeed6 @ Jan 21 2010, 06:19 AM) index.php?act=findpost&pid=1631252
Any power gain difference between the NPG and the cp-e headers? How was the install on the NPG, any modifications you have to make to get them to fit, how about CELs? Sounds nicely matched with the Injens. Try playing both of your videos at the same time but side by side, you get a great comparison of sound.[/b]
I never tried playing them side by side, lol, I'll try that. I can't comment on CPE headers because I've never had them, nor do they fit on my car. As for installation of the NPGs, apparently the 6 came with 2 different EGR tube thread pitches, some has a fine pitch and some has a coarser pitch. Mine has the fine pitch but the headers have the coarse pitch, so it didn't work. I contacted Joey at Nautilus and he immediately got an EGR tube and put a fine pitch thread fitting on it and shipped it to me. The downstream O2 sensor wiring also has to be extended, and holes have to be drilled and bungs welded in after the main cats. Other than that it worked and fit fine. I've driven it at many different rpms and on extended drives and haven't seen the CEL come on.

NPG only designed a set of headers for the '06-'08, not for the '03-'05. So you'll have to get the MSDS ones (which you can also get from NPG's website), which are slightly different. The '06-'08 exhaust goes directly underneath the oil pan (the oil pan has a cut out for it) and routes underneath the subframe, while the '03-'05 exhaust goes around the oil pan and routes over the subframe. The MSDS headers are made of mild steel while the NPG ones are stainless steel though, so the MSDS are cheaper. But if you get the optional ceramic coating for the MSDS, they end up costing about the same.
 

·
Registered
Joined
·
206 Posts
Discussion Starter #7
Now I know that they dont make the Injen cat back any more, is there something comparable to that?
 

·
Registered
Joined
·
102 Posts
I am new to the exhaust modification idea hence little lost here ....NPG website says that MSDS Header Kit w/ Hi-Flow Catalytic Converter is off-raod only. Is it because it doesn't have pre-cats ? Also what's the point of Check Engine Elminators Set if it's for off-raod use only? Istalling CEL eliminators won't let me pass emisions right ?

I guess my question is if there is a way to exchange the whole exhaust system to high flow one and still pass emissions?
 

·
Registered
Joined
·
2,854 Posts
QUOTE (Drogos @ Jan 22 2010, 09:32 AM) index.php?act=findpost&pid=1631516
I am new to the exhaust modification idea hence little lost here ....NPG website says that MSDS Header Kit w/ Hi-Flow Catalytic Converter is off-raod only. Is it because it doesn't have pre-cats ? Also what's the point of Check Engine Elminators Set if it's for off-raod use only? Istalling CEL eliminators won't let me pass emisions right ?

I guess my question is if there is a way to exchange the whole exhaust system to high flow one and still pass emissions?[/b]
They only put "off-road only" to cover their asses, because I don't think it's legal in some places to mess with emission control components. Now they can say that they sell the product for off-road only, but they can't be responsible for what the buyer uses it for. I guess a reason you want to have CEL eliminators is so you don't have to worry about what the CEL is for. Even if you know that the headers are throwing a CEL, you won't know if anything else is throwing a code as well, since it's the same light.
 

·
Registered
Joined
·
2,907 Posts
I love my Racing Beat mufflers. Well, after I did a bit of sound deadening....... They have no trace of fart car from outside the car, but inside the car they were a bit boomy. That could be because I have a wagon and it's essentially one big passenger compartment. I don't have a trunk to kill the muffler sound.... I undercoated the cargo area and even trunk-painted the spare tire well.

Anyway, outside they sound great. Nothing that sounds like a 20 year old ricer in a Civic.

I've got a set of MSDS headers I'll be putting on and I'll definitely be running a (Magnaflow ceramic) cat. Not only for at least a bit of emissions, but also because the non-cat cars on YouTube do not sound good.
 

·
Registered
Joined
·
2,907 Posts
QUOTE (Drogos @ Jan 28 2010, 08:11 AM) index.php?act=findpost&pid=1632921
care to share some more details ??? I have a wagon too and there is exhaust exchange high up on the "to do" list so any hint would be highly appreciated[/b]
On the cargo area I used trunk paint from side to side, and from just inside the hatch lip to underneath just at the back seat. http://forum.mazda6club.com/index.php?s=&a...t&p=1631660


As for the undercoating, I started by first putting it (the back) up on stands ramps, removing the wheels and wheel well liners, then dropping the exhaust (not unbolting, but simply undid the hangers at the mufflers and just ahead of the 'Y', then lowered it a bit using my floor jack) I used a somewhat weak mix of Simple Green and scrubbed-down everything around the mufflers and in the wheels wells.

Between the warm weather and using a compressor blow gun it was dry in no time. I taped-off the suspension, and just where the body wraps back under the car. Basically think of it like this- picture you're looking into the wheel well, and where the body comes straight down, just before it turns back under the car, I used tape and newspaper to block that off so it looks like a curtain of newspaper. I also taped-off around the fuel filler neck.

I then simply used 3M rubberized undercoating. I want to say 2 cans...... The underside of the cargo area, from the rear sub-frame to just ahead of the rear bumper bar, side to side, is undercoated. Same with both wheel wells.

It definitely made a difference. Heck, even the sound of rain/wheel splash is reduced.
 
1 - 13 of 13 Posts
Top