Like a lot of you I waffled about this a long time like I did the Header upgrade. Really didn't want to spend that kind of money without KNOWING I would get some benefit. Other mods that's easier to see.
My stock headers where ticking, so when Rob (RobRed) tested the DT headers I saw a significant improvement and decided it was enough to warrant the investment. For those that hadn't seen it, here is the thread with the results.
I saw that you had to loosen the engine mount and there were some other install difficulties. I decided to have Robbie install these and it took him most of the day. Glad I did that.
When I drove the truck, I did notice a difference in performance. It is easy to see as my daughter also has a 2004 LC.
I then saw Baktash's thread on the CAT Back. He initially was coming across a bit over the top on marketing, but when I talked to him on the phone, he seemed like a pretty good guy and I have talked to him several times since then and still feel that way.
EMS Catback, like DT headers were beautiful looking and well made products. I thought it was awesome to have new vendors for this market where a few years ago it was hard to find anything.
I DIDN'T NEED a new exhaust, but I have 140K miles and my truck and it will probably fail any day now . . . . right?
Yet, I was hesitant because I couldn't place the value in my mind. EMS had some Dyno plots posted, but I take vendor test results with a grain of salt.
RobRed stepped up again and using a DT Header truck as the baseline did all sorts of runs with the DT Catback, EMS Catback and EMC midpipe and catback. It clearly showed to me the biggest performance improvement was the EMS midpipe and catback. The DT system performed well too, but I selected the EMS system. Having this independent set of test data was very helpful. I am an engineer by education so data is great. Here is Rob's post with data plots
I was sold .. um wait, how many CATs do I want? Do I want a resonator instead of a CAT? Do I want a Silencer? Geeeez, where was the data on this? I ended up with no silencer and two CATs. I wanted to make sure I was compliant and the performance hit of a 2nd CAT didn't seem to be much. It was a judgment call. From reading the reviews in the main thread it seemed most where not satisfied with the silencer, so I passed on that knowing I could add something later.
So I put my order in and two boxes shipped the same day, made it to the local depot last Thursday for a Friday delivery. When the man in Brown came Friday with the Catback box, I asked where the other one was. Turned out the men in Brown left it at the Depot and I wouldn't get it till Monday.
So removed everything and installed the CAT Back Friday and Monday night installed the Midpipes. The system fit well on my truck. It idles nice and isn't loud, just a low rumble.
I know , make some sound clips. Nope I don't do that. But I will tell you when I drove it today the thought that popped into my mind was it sounds like a 1972 Mustang Mach 1 (Always wanted one). It's fairly quiet at idle and steady state while driving. You can hear it when you accelerate and like I said it sounds like a muscle car. Not obnoxious, but not quiet. It is a personal decision if that works for you. I am still deciding.
The one thing I decided is based on the way its made and assembled, its easy to remove the rear pipe and insert another muffler or component if I decide to quiet it down a bit. I had the same dilemma with a custom exhaust on my 97 Supercharged land cruiser and ended up adding a glass pak at the end.
I want to put some highway miles on it and then decide what I want to do.
I do want to be clear, this is a performance exhaust and sounds like one. Nothing wrong with the product if it is too loud for us personally, but fortunately it is easy to customize on our own
I think it would be great to have a thread on solutions some of us did to customize. I have used a glass pak before and I see Lesgarten posted this Moroso Spiral Flow Muffler as a potential solution and it looks like 008N used it with some improvement, but he had no CATs so results will likely vary
Don't mind the red in the Pics, that's not rust. Just memories of Moab
My stock headers where ticking, so when Rob (RobRed) tested the DT headers I saw a significant improvement and decided it was enough to warrant the investment. For those that hadn't seen it, here is the thread with the results.
I saw that you had to loosen the engine mount and there were some other install difficulties. I decided to have Robbie install these and it took him most of the day. Glad I did that.
When I drove the truck, I did notice a difference in performance. It is easy to see as my daughter also has a 2004 LC.
I then saw Baktash's thread on the CAT Back. He initially was coming across a bit over the top on marketing, but when I talked to him on the phone, he seemed like a pretty good guy and I have talked to him several times since then and still feel that way.
EMS Catback, like DT headers were beautiful looking and well made products. I thought it was awesome to have new vendors for this market where a few years ago it was hard to find anything.
I DIDN'T NEED a new exhaust, but I have 140K miles and my truck and it will probably fail any day now . . . . right?
Yet, I was hesitant because I couldn't place the value in my mind. EMS had some Dyno plots posted, but I take vendor test results with a grain of salt.
RobRed stepped up again and using a DT Header truck as the baseline did all sorts of runs with the DT Catback, EMS Catback and EMC midpipe and catback. It clearly showed to me the biggest performance improvement was the EMS midpipe and catback. The DT system performed well too, but I selected the EMS system. Having this independent set of test data was very helpful. I am an engineer by education so data is great. Here is Rob's post with data plots
I was sold .. um wait, how many CATs do I want? Do I want a resonator instead of a CAT? Do I want a Silencer? Geeeez, where was the data on this? I ended up with no silencer and two CATs. I wanted to make sure I was compliant and the performance hit of a 2nd CAT didn't seem to be much. It was a judgment call. From reading the reviews in the main thread it seemed most where not satisfied with the silencer, so I passed on that knowing I could add something later.
So I put my order in and two boxes shipped the same day, made it to the local depot last Thursday for a Friday delivery. When the man in Brown came Friday with the Catback box, I asked where the other one was. Turned out the men in Brown left it at the Depot and I wouldn't get it till Monday.
So removed everything and installed the CAT Back Friday and Monday night installed the Midpipes. The system fit well on my truck. It idles nice and isn't loud, just a low rumble.
I know , make some sound clips. Nope I don't do that. But I will tell you when I drove it today the thought that popped into my mind was it sounds like a 1972 Mustang Mach 1 (Always wanted one). It's fairly quiet at idle and steady state while driving. You can hear it when you accelerate and like I said it sounds like a muscle car. Not obnoxious, but not quiet. It is a personal decision if that works for you. I am still deciding.
The one thing I decided is based on the way its made and assembled, its easy to remove the rear pipe and insert another muffler or component if I decide to quiet it down a bit. I had the same dilemma with a custom exhaust on my 97 Supercharged land cruiser and ended up adding a glass pak at the end.
I want to put some highway miles on it and then decide what I want to do.
I do want to be clear, this is a performance exhaust and sounds like one. Nothing wrong with the product if it is too loud for us personally, but fortunately it is easy to customize on our own
I think it would be great to have a thread on solutions some of us did to customize. I have used a glass pak before and I see Lesgarten posted this Moroso Spiral Flow Muffler as a potential solution and it looks like 008N used it with some improvement, but he had no CATs so results will likely vary
Don't mind the red in the Pics, that's not rust. Just memories of Moab

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