Exhaust System Installation (Borla)

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Borla 350Z True Dual Exhaust

Introduction

This installation guide is for the Borla dual exhaust system for the Nissan 350z. However, the same procedure can be used to install almost all of the exhaust systems available with minor differences. Specifically, the stock exhaust removal section will be the same no matter what exhaust system you decide to install on your 350Z. I have tried to capture the entire process in detail so people can judge for themselves if it is worth paying someone else to do it, or tackle this job on their own. I highly encourage people to work on their own cars and I hope that is reflected in my tutorials.

• My Review
• Borla

Tools and Materials

These are some things you will need.

• Various sockets: 10mm,12mm,14mm,15mm
• Socket wrench
• Torque wrench
• Screw drivers
• Adjustable pliers
• High Temp gasket sealant
• WD-40 lubricant
• Gloves
• Work or throw away clothes
• Floor jack
• Jack Stands (4)

The Procedure

The installation procedure has been broken down into several sections. I have tried to lay it out so nothing is missed. Many of the steps are obvious, but I have included them to demonstrate what is actually involved in the process. The installation took me around 3-4 hours, which included stopping every few minutes to snap pictures and dump them onto my PC. Expect a 2-3 hour install if you are working alone. 1-2 hours is possible if you bring a friend.

The first thing of course is to get the 350Z in a workable position. The best way is getting her on a lift, but it is highly unlikely anyone has a lift in their garage. But if you have access to one, use it. The typical at-home method is to get the car up on jack stands. I decided it was best to use 4 stands and have the car parallel to the ground. I raised it up as high as I felt it safe on the stands. Be sure you can get underneath and move around easily.

You will be moving around a lot so a rolling sled of some type will help. However, I found it didn't help so much when I was pushing and pulling to get the exhaust into place. I kept rolling around and ditched the sled at this point.

Removing the stock exhaust

1 Center Brace Removal
First we are going to make room to bring the stock exhaust down. The Borla instructions tell you to take out the center cross brace. Looking at it for awhile, it looks like you dont have to take it down, but it is probably a good idea unless you want to start cussing because you cant quite get things into place. So The first step is to remove this brace.

1.1
Needed: 10mm socket, socket wrench
There are 2 plastic covers that you need to remove in order to get the brace off (1 per side). Each plastic cover is held on by 2 nuts and 1 bolt. All are 10mm. This step is pretty straight forward, so if you need more explanation here, then you should probably get some help before proceeding.

1.2
Needed: 12mm socket, socket wrench
Once you have the plastic covers off (step 1.1), you will see six(6) 12mm bolts holdint the rear sections of the brace to the frame (3 per side). You can take these out and not worry about the brace dropping because it is still held on the front by 4 bolts. Also, on the rear end there is a slot that the brace fits into to hold it up.

1.3
Needed: 14mm socket, socket wrench
At the forward end of the cross brace is four(4) 14mm bolts. These ones were torqued down pretty good and took a little more effort to remove them. Loosen all bolts before taking them out. Finally, before you remove the last one, make sure you have the brace held in place or it will drop on your face. Don't say that I didn't warn you. Once the bolts are out, carefully remove the brace and set it aside for later.

1.1

1.2

1.3

2 Remove Pipes
The next step is to unbolt the exhaust components. After the bolts are removed we can pull the different sections down a piece at a time. The muffler removal has its own section (3) because it is more involved.

2.1
Needed: 14mm socket, socket wrench
Just in front of the muffler there is a flange connection that we need to unbolt. There is also a ground connection here that we will need to reconnect on the new exhaust later. Use the 14mm socket and wrench to take the nuts off. The bolts are fused to the exhaust and can not be removed. At this point we still can not take any exhaust components down.

2.2
Needed: 14mm socket, socket wrench
Unbolt the Y Pipe from the rear mid pipe section. At this point you can remove the rear mid pipe. It will take some wiggling because the bolts are fused to the flanges. But it comes out fairly easy.

2.3
Needed: 14mm socket, socket wrench
Finally, the last bolts that need to be removed are at the catalytic converter / y-pipe connection. I am not 100% sure these are 14mm, but judging from the rest of the exhaust bolts I am guessing yes. Because my Z has test pipes, it has different nuts and bolts. Make sure you are supporting the y-pipe somehow before you fully remove the nuts. Take the y-pipe down and set it aside.

2.1

2.2

2.3

3 Remove Muffler
Needed: adjustable pliers, WD40, screwdriver, floor jack, towel
Now it is time to drop the muffler. I am still not sure what the best way to do this is. This was the most difficult part of the entire project and had me using quite a few bad words. The muffler section is held in place by 4 hangers and rubber grommets. I found it helped significantly to spray some WD40 into the rubber grommets to help the hangers slip out easier. After pushing, pulling, screaming, cussing and other things, I found out the best way to get the hangers out of the rubber grommets was to use some wide-jaw pliers and just squeeze them through. I slid the front two hangers out, then debated on how to hold the muffler up while I finish up the final two.

I took my floor jack and placed a folded shop towl over the jack pad and raised it up just enough to support the exhaust muffler. Looking at the pictures, you can see that the final two hangers were very hard to reach with the pliers, but since I played a lot of Tetris over the years I managed to work the pliers into place and squeeze the hangers loose. Lower the jack while holding the exhaust steady and the process of removing the stock exhaust is complete.

3.1

3.2

3.3

3.4

Installing the Borla exhaust

Prep
The first thing of any big installation is to make sure you have all the parts. Nothing is worse than getting you car torn apart and 3/4 done, then realizing you are missing a critical component to finish the job. It's like finding out you only brought one shoe 5 minutes before the start of a marathon. I took the exhaust and laid everything out, and even matched it with the parts list and drawing.

There has been complaints in the past of the Borla exhaust leaking due to excessive use of clamps. There are 9 total clamps and since I did not want do this install over again, I purchased some high temp gasket sealant. You can get this from any auto parts store. Just make sure it is high temperature or you will burn it off, or worse catch something on fire.

Borla does not include any gaskets, so we are left with either buying new ones from the dealership, making our own, or reusing the stock gasket. Since I am using the gasket sealant, I decided to go with the stock gasket and just goop it up real nice.

Parts check

Sealant

Old gasket

Front Pipes
The first step is to install the left and right front pipes. These came clearly marked "LH" and "RH" which is nice. Since I have test pipes, the steps here may be slightly different than for people with stock cats still in place.

Use the gasket sealant on the test pipe flange, and the front pipe flange. Goop it up real nice but stay away from the pipe inner diameter (I.D.) You don't want to get a bunch of this in the exhaust flow. Put both bolts thought the test pipe flange and place the stock gasket. The bolts will help hold the gasket into place while we move things into place. Next take one of the front pipes and put into place to meet the gasket. Hand tighten both bolts enought to hold everything in place. At the end we will go back and torque things down.

Below you can see both front pipes in place. Notice they do not appear to line up. This is okay because we have not tightened up the bolts yet, and need the wiggle room to get the rest of the exhaust into place.

Front pipes

Goop up the flanges with the gasket sealer

Front pipes in place

H Pipe Assembly
The first thing to notice is the H-Pipe crossover uses a smaller clamp than the rest of the pieces. So find the smallest clamp of the bunch and set it out for quick use. The short end of the pipes face forward. If you notice this end is larger in diameter than the rear end so it can slide over the front pipes. The larger diameter portion of all the pipes are split (see below) to allow the clamping force to seal things up. Use the gasket sealant in 3 places for this step: 1 pipe on the h-pipe crossover, and 2 pipes on the forward edge where it connects to the front pipes. Place the small clamp over the crossover and slide the h-pipe pieces together. Slide 2 clamps onto the front pipes, then take the assembly and slide it together with the front pipes. Push it as far forward as you can, or you will run out of space when you get to the muffler like I did. Do not tighten anything yet.

H-pipe is an assembly that comes in 2 pieces

Small clamp goes on H-Pipe connect

Clamp split

Sealant on inside of clamp area

Front Mufflers
This step was pretty quick. These are more appropriately called resonators, but Borla has them labeled as front mufflers. Just use the sealant on the forward inside edge of the pipes (where the clamp goes) and slide them up onto the H-Pipe assembly. The tricky part is figuring out which pipe is left and right because they are not labeled. In the pictures below, I think i have it correct. You will notice that one pipe has a kicked out pipe at the back which is the right side muffler. Also you can rotate the pipes and it affects where the pipes line up in the back. But this can be adjusted once we have everything in place.

Front mufflers

Notice the kick on the right muffler

Mid Pipes
Needed: WD40, pliers, Beer
Again, this step is pretty straight forward. The pipes are clearly labeled "LH" and "RH". Take the gasket sealant and goop up the front inside edge of the pipes (larger diameter end with splits). Put a clamp over the front edge and slide the left pipe onto the left forwart muffler. Insert the hanger into the rubber grommet where the stock exhaust used to hang. I sprayed some WD40 onto the grommet to help push things into place and squeezed it with some pliers.

The right pipe needs to go over the rear sway bar. Place a clamp over the forward edge and slide it through and onto the the front right muffler. Again spray some WD40 onto the grommet and squeeze the hanger into it. I ran into trouble here because I did not push all the pipes together well and it left me a bit short to reach the grommet. I had to force things to work.

Hanger

Another hanger

Muffler
Needed: WD40, pliers, floor jack, shop towl, 15mm socket, socket wrench
Ok, we are almost done. I used the floor jack and shop towl to raise the muffler into place. A friend would probably work better but since I don't have any a machine will have to do. Make sure you use the gasket sealant on the clamp areas again before you go to far. Slide the final two clamps over the pipes and wiggle everything into place.

Now the hard part. You have to get the hangers to fit into the rubber grommets. Again, because I didnt squeeze things together as well as I should have, things came up a bit short and it was pretty tough to get things to line up. Don't fret, once you get past this step it is smooth sailing the rest of the way.

The final step here is to make sure you hook up the ground wire. You will have to remove the bolt from the clamp, insert the ground wire loop, and bolt things back together.

Muffler

stupid hangers

Ground wire

Double Check and Torque
Needed: torque wrench, 15mm socket, socket wrench
Now is the last chance you have to make sure things are lined up where you need them. Make sure everything has good clearance, especially around the rear suspension components. Twisting the front mufflers helped me get some additional clearance. Once you are happy with how everything looks, go torque down all the clamp bolts. Borla states 32-35 ft-lbs on the clamps. I used the same on the flanges at the test pipes.

You are pretty much done at this step. If alot of sealant was squeezed out from the clamps, go back and wipe it down just for good measure. If you work like me, you probably have tools all over the place and now is time to clean up. You are also very dirty at this point, so don't even think about getting in the Z and starting her until you get showered and into some fresh clothes.

Finished

For comparison, here are before and after images. I will be uploading a sound clip and video as soon as I get a chance to shoot it.

Stock Exhaust

Borla Exhaust

Borla Instruction Scans

Here are scanned images of the Borla paperwork that comes with the exhaust. Included is an introduction, installation instructions, and parts list. I felt the instructions were adequate to get started, but really did not cover any real world troubles one might have when doing this.

Introduction and typical disclaimers	System drawing with parts list	Stock exhaust removal	Removal continued
Borla installatio	Install continued	Finished picture	Parts and assembly list
Another drawing and list