My Exhaust Upgrade DT headers and EMS mid pipe and Cat Back

[Romer]

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

 

[Romer]

so some thoughts on the install. First I wished I had bought one of these first. $15 would have been worth the PIA getting these off was.

A sawzill definitely comes in handy. Used PBblaster, but on the long pipe with hard bolts, just cut it up. Made the removal much easier

The hard part was I have the Slee Skid plate system and you have to remove the middle and belly plate to do this install. The belly plate is 95 lbs and I am not a young guy anymore. So I came up with a scheme to use leverage on this 95lb plate. Bench pressing and working the bolts would have been hard.

You may be able to do the catback with the Slee belly plate in place, but it would be tough and require small hands. The mid pipes require the belly plate removal.

So I followed Christos instructions and did the reverse of the install. I modified it a bit. I removed the middle plate and got a block of wood and a jackstand tight under the tranny pan and then I let about 10 lbs of pressure out of my front tires to make it tight and non movable. I then put my floor jack under the belly plate with two jack stands at the other side. You have to support the tranny because the Slee belly pan replaced the crossmember and when you take off the plate, you are removing part of the tranny support system

I loosened all the bolts and then took out all but the 4 corner ones.

I then took out the two on the side where the floor jack was and lowered it down a bit, then took out the two on the side with jackstands and lowered it down on the jackstands. Then lowering the jack a bit more. Moving the jackstands I was able to slide it out of the way of the drivers side which required greater access. It is still on the floor jack and two stands so I can swivel it back and raise it by myself for the install. A couple of pics below

Getting the middle plate off wasn't two bad. I did use the floor jack for leverage to raise it up while I bolted it on.

The setup itself did go on pretty easy. During the removal of the old system I had to disconnect one of the O2 sensors and I left one on. During the install getting the O2 sensor on the midpipe after it was on the truck was a PIA. I recommend installing the O2 sensor before hand.

I have the Slee Rear bumper and couldn't get the last hanger to work based on clearnaces. The rubber hanger was on two posts so I took it off and installed it on the lower post and it seems to work fine. Pic below

 

[oftpiste]

that's one purty exhaust.

 

[Romer]

I did have one question and sent it to Baktash suggesting he include instructions. The install is pretty straight forward, but I was stalled for a bit

The point where the midpipes attach to the Header had me stumped for a bit.

The OEM midpipes have a groove and an extension of the pipe like shown in the picture. This enables use of the donut type OEM gasket. EMS midpipes are flat with no groove. I played with using the gasket, but it didn't seem to work. I ended up bolting the flat EMS midpipes to the Flat DT headers with no gasket and tightened it down. Seems to work fine. I am assuming if I had a leak there I would hear it and it doesn't seem like there is anything.

 

[Romer]

Overall very happy with the Quality of the product. - Excellent

Needs a set of instructions even though 95% of it is obvious. The bolts and funky fittings to go on the other side of the header to capture the nut were not obvious. The old nuts where still on the headers so I didn't need them and the gasket issue I mentioned - Needs work

Shipping was quick and on time - Excellent

Product was packed extremely well - Excellent

Sound performance is a personal preference and I am still undecided. Like I posted earlier. Any modifications should be easy to just remove the rear pip and add something there. I am guessing Baktash could do this or a regular muffler shop. Not a factor in rating since it sounds like a performance exhaust

Improved Performance - Excellent

Who wants to start a thread on their customization of the EMS, DT or even a custom exhaust to work on noise levels vs performance hits?

 

[mechanixhorseman]

I've got the full DT setup, headers, catback and all. I toyed around with the idea of some extra noise deadening in the cargo area to put the slight drone at 2000k at bay, but isn't really noticeable enough to bother me. I may do so in the future when time becomes more available and I'll post something if I have any progress.

 

[farinvail]

Romer, nice write up. Looks beautiful.

 

[Romer]

Romer, nice write up. Looks beautiful.

Thanks Farnham

Curious what others did from the midpipe to header interface, did you just bolt metal to metal?

 

[RobRed]

Thanks Farnham

Curious what others did from the midpipe to header interface, did you just bolt metal to metal?

I used the supplied gaskets with the mid-pipes.

 

[NKP Garage]

Thanks Farnham

Curious what others did from the midpipe to header interface, did you just bolt metal to metal?

I shipped you a new pair of the donut gaskets that go between the midpipes and headers.

Here's a photo of the donut gasket situated on the header flange. The EMSPowered midpipe does not have the pipe protruding out of the end like the stock midpipe. So when you are doing the installation it helps to out something sticky such as a very small dab of RTV on the donut gasket to keep it in place on the groove in the header flange while maneuvering the midoipe into place.

Give me a call or PM if you have any questions.

 

[Romer]

I used the supplied gaskets with the mid-pipes.

Thanks Rob, I didn't get those gaskets in my shipment. That's where the instructions would have told me I am missing something

I shipped you a new pair of the donut gaskets that go between the midpipes and headers.

Here's a photo of the donut gasket situated on the header flange. The EMSPowered midpipe does not have the pipe protruding out of the end like the stock midpipe. So when you are doing the installation it helps to out something sticky such as a very small dab of RTV on the donut gasket to keep it in place on the groove in the header flange while maneuvering the midoipe into place.

Give me a call or PM if you have any questions.

Thanks Baktash for getting those out quickly.

Do we know the DT headers have the Groove, I thought they were flat? The OEM midpipes also had this groove but yours did not

 

[joe dirt]

Great info, and thanks for sharing.

 

[NKP Garage]

Thanks Rob, I didn't get those gaskets in my shipment. That's where the instructions would have told me I am missing something

Thanks Baktash for getting those out quickly.

Do we know the DT headers have the Groove, I thought they were flat? The OEM midpipes also had this groove but yours did not

Good question. I know the stock headers have the groove. Not sure if the DT headers do or not from memory.

 

[NKP Garage]

Looking at photos it looks like the DT headers have the groove like the stock headers.

 

[Romer]

Looking at photos it looks like the DT headers have the groove like the stock headers.

Thanks and thanks for sending out the gaskets. I don't think there is a leak at this interface, but I will put them in next week when they come

 

[RobRed]

DT headers do NOT have the protruding pipe to center the gasket. I'm speaking about the second run DTs.

 

[NKP Garage]

DT headers do NOT have the protruding pipe to center the gasket. I'm speaking about the second run DTs.

The header flange shouldn't have a protruding pipe. It should have an inset groove. Take a look at the photo I posted above of the stock header flange.

 

[Romer]

The header flange shouldn't have a protruding pipe. It should have an inset groove. Take a look at the photo I posted above or the stock header flange.

So I appreciate the two day air on the OEM gaskets.

Here is the way this setup was designed by Mr Toyota

This stock mid pipe has a grove to hold half the donut style OEM gasket. It also has a protruding pipe to hold the gasket to insure proper placement for seal

[URL="https://forum.ih8mud.com/attachment.php?attachmentid=792828&stc=1&d=1376445911"][/URL]

The headers (DT Headers in Pic) also have a grove to hold the other half of the OEM Donut gasket

[URL="http://i135.photobucket.com/albums/q151/masimatt/IMAG0213_zps2d0d05b0.jpg~original"][/URL]

Now picture the Donut OEM gasket riding the small pipe half in the mid pipe and half in the header making great contact. The flat part beyond the center can have a gap or be touching as long as this type of seal is in place

Now I believe the EMS midpipes in the design process did not consider this. I tried the RTV to hold on the gasket, but wasn't quite able to get the nuts thread started because the gap was larger between the flat part of the header and the midpipe, why, because instead on the donut being recessed on the midpipe, it is flat with the entire surface. See picture below.

With nothing to center, it would be quite easy for the oem donut to move a bit even with the recess in the header pipe. I played with it and I see the potential for there to be an airgap on the midpipe side because the hole is bigger if the gasket moves just slightly.

Even if it is lined up, I don't see the seal being any better, in fact I think it is worse then no gasket. Why, the midpipe side is riding on the flat surface creating a gap at that same surface due to the height of the gasket pushing against the header. More surface contact occurs without the gasket.

So I removed the gasket and put it back metal to metal. How would I easily tell if there is a leak there. Climbing underneath while running I do not see or smell anything at this junction.

I hope EMS looks at this interface going forward. Maybe I am wrong and I welcome someone to poke holes in my thoughts here.

 

[Romer]

So far the metal to metal seems to be fine at this interface, but again I have no tools to test for a leak.

On the positive side, I put a couple 100 miles on it, 150 on the highway doing 80-85 (It is the west) and decided I am quite happy with it and won't do anything to quiet it down

Even with the above item, I would still recommend these, but I would like to see EMS address this

 

[Romer]

Id really like to hear from someone else who installed midpipes in their garage to see what you did