99'Subourbon
Longroof NOOA Member
I recently did the install and thought I would share the setup for anyone else looking to do a full exhaust system on their Suburban’s (should work for any gmt400 year). This may also work on trucks and Tahoe’s, but I don’t have hanger locations or cross member locations to compare. I don’t believe it would be far off though, and could be made to work with some minor cutting and additional welding. However, I went this route with the understanding I was getting a tune, and removing my cats and rear 02 sensors. If you need both of those things, then you’ll have to come up with a solution to that.
I went this route because the only local exhaust shop wanted $600 just to fab up a crush bent Y, and weld it on to the muffler, dumped immediately. I knew I could buy a welder and get a full exhaust system for around that same amount of money (less than $800).
Everyone recommends hooker LTs, but I didn’t want to deal with the hassle of LTs, but did want to get as much performance as I could. I also didn’t want to buy overpriced Vortec specific headers, so I went with TBI headers.
I went with Flowtech mid-length afterburner headers. These are supposedly providing the benefits of long tubes, with great scavenging properties. I also chose these because they also have a Y-Pipe that you can use with them that goes into 3”.
Here is the headers and y-pipe-
Headers: http://www.summitracing.com/parts/big-49156flt
Y-Pipe: http://www.summitracing.com/parts/big-49156yflt
As a note, the y-pipe comes raw, not ceramic coated as shown. The headers are stated to come with black high temp paint. I called Holley and asked regarding it, and they claimed it is true high temp paint. I’ve heat soaked and cycled the headers multiple times now, and the only ever smoked, which was them curing/baking in I guess. The black paint has not burnt off and still looks good – YMMV. If you’re concerned, order the more expensive set or paint them yourselves. I opted not to since we don’t salt our roads here.
I purchased both off amazon for less money, with stage 8 8911 header bolts; Total of $470.45 after Tax + S/H.
Then I needed the piping, which I was gonna do a universal kit at first, but I found dynomax actually sells intermediate and tailpipe prefabbed pieces for all of our trucks.
For the intermediate pipe: http://www.summitracing.com/parts/wlk-53014
For the tail pipe: http://www.summitracing.com/parts/wlk-45670
Again I purchased both of these off amazon for less; Total of $94.69 after Tax + S/H.
Next you’ll need a straight piece of pipe, but no more than 4’, so I bought this:
Jegs 3”x4’L: http://www.jegs.com/i/JEGS-Performance-Products/555/30611/10002/-1
Amazon had it in stock ($16.99).
You’ll also need:
1x 3” exhaust tube coupling (Vatozone, $5.99)
1x 3” Exhaust Clamp (Vatozone, $5.99 -if you want to be able to separate it without cutting)
1x Tube of Silicone based copper hi-temp gasket maker (this is what I used, for added sealing, you may already have it)
The headers and y-pipe come with high quality carbon based gaskets, which I opted to use. If you are concerned, I suggest remflex gaskets. If I went remflex, this is what I would use.
Remflex Gasket: http://catalog.remflex.com/CHEVROLET_GM_CHEVY_Header_Exhaust_Manifold_Gasket_p/2021.htm
These will match the headers.
For a muffler and tip, that is up to you, and can cost $30 - $200+. I went with a Dynomax Ultra-Flo 17220 and Tip (Total $114.49 after Tax + S/H).
Muffler: http://www.amazon.com/gp/product/B00029J3DO/
Tip: http://www.amazon.com/gp/product/B0052XN2RI/
Total cost of $708.60 (For Headers, Y-Pipe, Full over-axle, mandrel bent, exhaust + Tip)
You may or may not already have a welder, but I got the harbor freight 115v 90a Flux Core Welder for $86.99 + tax, if you include this in the cost, I am still below $800.
-----------
Installation:
I didn’t take pictures during the install process, but I’ll give you what I have.
These headers were a breeze to install. The most trouble I had was getting out the header bolts from the factory manifolds. I stripped a portion of the threads off the first 2 and stopped. Then sprayed the rest with WD-40 4 times over the course of 1.5 days – then they came out without any issue, and very easily.
Before removing the manifolds, I suggest removing the spark plugs and sparkplug wires, to keep from accidentally breaking them during the removal of the manifolds, and during installing your headers. If you haven’t done a tune up recently, now would be a good time. I installed the headers from underneath, and they slid right into place without any clearance issues. I only had to remove the ground strap on the passenger side. Once they are installed, you can put it right back where it was.
Driver Side
Passenger Side
The passenger side header will need a 02 bung installed, but it’s right in line with the stock location, so no extensions are needed. Here you can see where I put it, which gives me easy access to it, and keeps the wire away from the heat.
Here is the flanges of the Y pipe connected to the headers, lined up perfectly, using their gaskets with no leaks.
And here you can see where the 3” coupler and clamp comes into play. I still need to weld one side of this, and you can see why I use the clamp here. You can opt to go with a flange, but I thought this was easier.
Then intermediate pipe is used to clear the cross member, which connects to the straight pipe, which is connected to the muffler.
Then the muffler is connected to the tail pipe.
I moved the hanger location on the body (It did line up in the stock location, just not ideal), to where it was more stable, and the welded on a 2[SUP]nd[/SUP] hanger simply because I wanted to really firm it up. You don’t need to do this.
Here the 2[SUP]nd[/SUP] hanger is exactly in the same stock position, and nothing was needed to be done. I simply cut off a portion of the tailpipe, and put on my tip.
I really like the way the exhaust came out. Surprisingly, it has no rasp what so ever, even without cats. It took me about 8hrs start to finish to get everything done.
Here is some pictures from under the hood of the headers.
I do have some leaks on some of the welds. The headers and the y-pipe are not leaking. I’ll post sound videos up later this evening.
I went this route because the only local exhaust shop wanted $600 just to fab up a crush bent Y, and weld it on to the muffler, dumped immediately. I knew I could buy a welder and get a full exhaust system for around that same amount of money (less than $800).
Everyone recommends hooker LTs, but I didn’t want to deal with the hassle of LTs, but did want to get as much performance as I could. I also didn’t want to buy overpriced Vortec specific headers, so I went with TBI headers.
I went with Flowtech mid-length afterburner headers. These are supposedly providing the benefits of long tubes, with great scavenging properties. I also chose these because they also have a Y-Pipe that you can use with them that goes into 3”.
Here is the headers and y-pipe-
Headers: http://www.summitracing.com/parts/big-49156flt
You must be registered for see images attach
Y-Pipe: http://www.summitracing.com/parts/big-49156yflt
You must be registered for see images attach
As a note, the y-pipe comes raw, not ceramic coated as shown. The headers are stated to come with black high temp paint. I called Holley and asked regarding it, and they claimed it is true high temp paint. I’ve heat soaked and cycled the headers multiple times now, and the only ever smoked, which was them curing/baking in I guess. The black paint has not burnt off and still looks good – YMMV. If you’re concerned, order the more expensive set or paint them yourselves. I opted not to since we don’t salt our roads here.
I purchased both off amazon for less money, with stage 8 8911 header bolts; Total of $470.45 after Tax + S/H.
Then I needed the piping, which I was gonna do a universal kit at first, but I found dynomax actually sells intermediate and tailpipe prefabbed pieces for all of our trucks.
For the intermediate pipe: http://www.summitracing.com/parts/wlk-53014
For the tail pipe: http://www.summitracing.com/parts/wlk-45670
Again I purchased both of these off amazon for less; Total of $94.69 after Tax + S/H.
Next you’ll need a straight piece of pipe, but no more than 4’, so I bought this:
Jegs 3”x4’L: http://www.jegs.com/i/JEGS-Performance-Products/555/30611/10002/-1
Amazon had it in stock ($16.99).
You’ll also need:
1x 3” exhaust tube coupling (Vatozone, $5.99)
You must be registered for see images attach
1x 3” Exhaust Clamp (Vatozone, $5.99 -if you want to be able to separate it without cutting)
You must be registered for see images attach
1x Tube of Silicone based copper hi-temp gasket maker (this is what I used, for added sealing, you may already have it)
The headers and y-pipe come with high quality carbon based gaskets, which I opted to use. If you are concerned, I suggest remflex gaskets. If I went remflex, this is what I would use.
Remflex Gasket: http://catalog.remflex.com/CHEVROLET_GM_CHEVY_Header_Exhaust_Manifold_Gasket_p/2021.htm
These will match the headers.
For a muffler and tip, that is up to you, and can cost $30 - $200+. I went with a Dynomax Ultra-Flo 17220 and Tip (Total $114.49 after Tax + S/H).
Muffler: http://www.amazon.com/gp/product/B00029J3DO/
You must be registered for see images attach
Tip: http://www.amazon.com/gp/product/B0052XN2RI/
You must be registered for see images attach
Total cost of $708.60 (For Headers, Y-Pipe, Full over-axle, mandrel bent, exhaust + Tip)
You may or may not already have a welder, but I got the harbor freight 115v 90a Flux Core Welder for $86.99 + tax, if you include this in the cost, I am still below $800.
-----------
Installation:
I didn’t take pictures during the install process, but I’ll give you what I have.
These headers were a breeze to install. The most trouble I had was getting out the header bolts from the factory manifolds. I stripped a portion of the threads off the first 2 and stopped. Then sprayed the rest with WD-40 4 times over the course of 1.5 days – then they came out without any issue, and very easily.
You must be registered for see images attach
Before removing the manifolds, I suggest removing the spark plugs and sparkplug wires, to keep from accidentally breaking them during the removal of the manifolds, and during installing your headers. If you haven’t done a tune up recently, now would be a good time. I installed the headers from underneath, and they slid right into place without any clearance issues. I only had to remove the ground strap on the passenger side. Once they are installed, you can put it right back where it was.
Driver Side
You must be registered for see images attach
Passenger Side
You must be registered for see images attach
The passenger side header will need a 02 bung installed, but it’s right in line with the stock location, so no extensions are needed. Here you can see where I put it, which gives me easy access to it, and keeps the wire away from the heat.
You must be registered for see images attach
Here is the flanges of the Y pipe connected to the headers, lined up perfectly, using their gaskets with no leaks.
You must be registered for see images attach
And here you can see where the 3” coupler and clamp comes into play. I still need to weld one side of this, and you can see why I use the clamp here. You can opt to go with a flange, but I thought this was easier.
You must be registered for see images attach
Then intermediate pipe is used to clear the cross member, which connects to the straight pipe, which is connected to the muffler.
You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
Then the muffler is connected to the tail pipe.
You must be registered for see images attach
I moved the hanger location on the body (It did line up in the stock location, just not ideal), to where it was more stable, and the welded on a 2[SUP]nd[/SUP] hanger simply because I wanted to really firm it up. You don’t need to do this.
You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
Here the 2[SUP]nd[/SUP] hanger is exactly in the same stock position, and nothing was needed to be done. I simply cut off a portion of the tailpipe, and put on my tip.
You must be registered for see images attach
I really like the way the exhaust came out. Surprisingly, it has no rasp what so ever, even without cats. It took me about 8hrs start to finish to get everything done.
Here is some pictures from under the hood of the headers.
You must be registered for see images attach
You must be registered for see images attach
I do have some leaks on some of the welds. The headers and the y-pipe are not leaking. I’ll post sound videos up later this evening.
Last edited:
