Sorry for my ignorance. I'm not very technical when it comes to performance upgrades. I want to add an exhaust to my 14 ATS AWD. There is a custom muffler shop that carries the Magnaflow muffler made for the ATS and they bend and weld the piping (of my choice diameter) there. Is there really any difference from buying it already made vs having it made? Any experiences with either route?
Custom Exhaust VS Aftermarket; Is there really a difference?
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I have had the same experience when I had my STi's there was a shop I always went to that carried MagnaFlow but they custom bent all there exhausts.....I put 4 different setups on my 2 Subies and I loved them. I don't think there is any difference other than it is already pre-cut for our cars.
I am a huge fan of MagnaFlow
I am a huge fan of MagnaFlow
In my younger days I had a Ford Thunderbird. I installed an aftermarket by Flowmaster which sounded good but had a lot of that drone sound. When I took it to my local shop they put one in that sounded 10X better than the one I had previously. Being a Cadillac I didn't want cheap out and end up unhappy but as I saw in another post piping is piping. Thanks for the input.
Well it depends... being as I have a 2.0... true duals are not really workable. A custom set was doable and cheaper but they were not SS. So I put in a Magna Flow system. I also removed the 2nd cat and mini muffler.
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But, I have 83 Monte Carlo SS and added dual auto trans cross member and had a set of 2.5" duals installed for 1/2 of what my Magna Flow setup cost and about the same as cat back system cost. Yea, V8 with a 8 into 1, cat and duals to the back. Talk about restrictive. Got to love the tree huggers of the 80's. Was a Al Gore born around that time?
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But, I have 83 Monte Carlo SS and added dual auto trans cross member and had a set of 2.5" duals installed for 1/2 of what my Magna Flow setup cost and about the same as cat back system cost. Yea, V8 with a 8 into 1, cat and duals to the back. Talk about restrictive. Got to love the tree huggers of the 80's. Was a Al Gore born around that time?
This thread has more detail on it but the exacts are 3" midpipe section feeding 2 Magnaflow 4x9 Center/Offset 2 1/4" mufflers, (11226)
all piping is mandrel bent and the total job was about $550
http://www.cadillacforums.com/forums/cadillac-ats-performance-forum/446329-any-exhaust-reviews.html
This is really simple. Muffler shop exhaust systems do not use mandrel bent pipes. That means that every place where the pipe is bent, it will have a slightly lower diameter, which will restrict exhaust flow. You can actually see this in the pix posted earlier on this thread. The good kits (Magnaflow, Corsa, etc.) will all have mandrel bent piping. Magnaflow also sells a "universal" kit that contains a bunch of mandrel bent tubes that can be pieced together by a local installer.
Also, muffler shop exhausts may not be stainless steal, which could rust through more quickly than you'd think depending on where you live.
Also, muffler shop exhausts may not be stainless steal, which could rust through more quickly than you'd think depending on where you live.
you can't speak on behalf of all muffler shops. the shop I visited frequently in the early-mid 2000s used mandrel bends, along with my buddy's shop in NC. maybe a lot of them don't but just ask if they have the proper machine for mandrel bends, along with stainless steelrhouse21 said:
^^^ in your set up where the flow is split into 2 streams of 2.5" pipes, if those bends are not mandrel, it probably doesn't matter. I would not want a non-mandrel bent pipe of 3" or less diameter if a single pipe were carrying all of the exhaust flow on a tuned/modified ATS.
Mandrel bends are inexpensive at Jegs/Summit along with true Y merges. At the point a custom exhaust is being done, might as well squeeze whatever gains can be had from it.
Mandrel bends are inexpensive at Jegs/Summit along with true Y merges. At the point a custom exhaust is being done, might as well squeeze whatever gains can be had from it.
Thanks, Ragtop.^^^ in your set up where the flow is split into 2 streams of 2.5" pipes, if those bends are not mandrel, it probably doesn't matter. I would not want a non-mandrel bent pipe of 3" or less diameter if a single pipe were carrying all of the exhaust flow on a tuned/modified ATS.
Mandrel bends are inexpensive at Jegs/Summit along with true Y merges. At the point a custom exhaust is being done, might as well squeeze whatever gains can be had from it.
My point is that if you are going to make the investment to "improve" your car, you might as well make sure you are actually getting an improvement. I s'pose I should have clarified that there is a difference between a "muffler shop" (translation: Midas) and a "performance exhaust specialist". One would probably have the right tools for a good exhaust while the other would not.
I'm a fan of the magnaflow products and have installed one of their complete systems (manifolds back) on my Camaro. High quality, good sound, and can be done in a driveway. A "performance exhaust specialist" could probably "hand craft" a pretty nice custom exhaust for you, but my experience is you are often rolling the dice unless you have actually seen a system from your chosen fabricator on the same car. And even then, you want to make sure you get the same guy who did the car you saw and hope he's not having a bad day.
Bottom line: These car's aren't cheap and it's easy to spend a lot of money for an "upgrade" that is just equal to or even worse than stock. I let some of the wrong people touch my Camaro over the years and it cost me heavily. I'm trying not to make the same mistake(s) with my ATS.
The MF's are mandrel 2.5". The custom on the SS is not but is 2.5" and that is up from 2.25". Large is not always better...^^^ in your set up where the flow is split into 2 streams of 2.5" pipes, if those bends are not mandrel, it probably doesn't matter. I would not want a non-mandrel bent pipe of 3" or less diameter if a single pipe were carrying all of the exhaust flow on a tuned/modified ATS.
Mandrel bends are inexpensive at Jegs/Summit along with true Y merges. At the point a custom exhaust is being done, might as well squeeze whatever gains can be had from it.
Here is what I am talking about.... The big ugly exhaust manifold is off my 5.7 Hemi and the nice 4 tube clam shell covered one is off a 6.1 SRT 8.
OBTW - Those case iron 5.7 exhaust headers weigh 13 lbs apiece.
Now toss in some down pipes.... Right 2.5" 5.7, center 2.75" 6.1 and left 2.75" high flow cats All have mandrel bends.
Finish it with a 2.75" SS Corsa cat back. You can see the ends of the down pipes at the bottom of the photo and the old 5.7 pipes to the right.
Does it make a difference.... Yes, this combo netted 362 rwhp based on advertised 370 hp measured at the crank.
The bottom line is... a good exhaust and tune with net you probably 30 or so new ponies.
I was talking about your ATS exhaust.
On my LS1 Camaro, I had my LT headers flow into an aftermarket 3" system with a mandrel over the axle pipe and muffler. I redid the exhaust with a true Y merge from the headers into a 3.5" pipe before going over the axle at 3". The true Y and 3.5" I-pipe helped the flow significantly. No before and after dyno, but my O2 readings showed the car running lean after the mods. I also included an electric cut-out for when every ounce of flow was needed.
I also agree that bigger is not always better as high gas velocities can help scavenging to the extent that can occur. On NA cars that is primarily a concern in header pipe sizing. On the ATS, post turbo I think the goal is minimize backpressure and so a big pipe or two big pipes seems like the way to go.
On my LS1 Camaro, I had my LT headers flow into an aftermarket 3" system with a mandrel over the axle pipe and muffler. I redid the exhaust with a true Y merge from the headers into a 3.5" pipe before going over the axle at 3". The true Y and 3.5" I-pipe helped the flow significantly. No before and after dyno, but my O2 readings showed the car running lean after the mods. I also included an electric cut-out for when every ounce of flow was needed.
I also agree that bigger is not always better as high gas velocities can help scavenging to the extent that can occur. On NA cars that is primarily a concern in header pipe sizing. On the ATS, post turbo I think the goal is minimize backpressure and so a big pipe or two big pipes seems like the way to go.
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