You could probably substitute most cat-back exhausts for this install, but this particular one happens to be the Valvetronic Exhaust, which retains the valved setup like the stock exhaust has, meaning when its closed exhaust is routed thru the muffler and has a near stock sound level. But when the valve is open, it bypasses the muffler and is pretty much a straight shot out. Anyways.
Step 1: Raise car off the ground using your preferred method.
Step 2: Make sure your exhaust valve is CLOSED, and then unplug the exhaust valve harness
Step 3: Next comes the fun part. Cutting the exhaust. On many BMWs, there is a little dimple on the pipe that is pretty much an indication for "cut here", but, of course my exhaust did not have the dimple, so I had to work it out myself. I pretty much just laid the new muffler on my chest and slid under the car and tried to work out where I thought the muffler was going to be when it was up on the hangers. Yeah sure this looks about right! LETS CUT!
No going back now
Step 4: Don't have pics, but now you can undo the nuts that hold the exhaust hangers on from each side. Loosen them up a little, then either have a helper hold one side, or brace it with something so you can unbolt the hangers and drop the muffler out.
Yep this is gonna be better
Step 5: Unbolt the 3 bolts that hold the exhaust valve motor on the stock exhaust and remove the motor.
Step 6: If you have OCD, CLEAN the motor
and then swap it over to the new exhaust. The Valvetronic kit comes with 3 new bolts, and a new spring. There is also a metal tray under the motor on the stock setup that you do not need to use on the new exhaust. Make sure the exhaust flap on the new exhaust is fully closed when you position the motor with the new spring and tighten it down. I was a gentleman and firmly held the flap closed w/ my thumb as I tightened down the motor. If there is any play in it, you open yourself up some awful rattling every time you fire the car up. You can also pull the exhaust mounts off the old exhaust and slide them onto the hangers on the new exhaust at this time.
Dont really have pics for the next few steps but,
Step 7: This system also comes with a coupler pipe to marry the 2 exhaust pipes together, so slide that on to one of the pipes, and again, either find a friend to hold one side of the exhaust or find something to hold it up with, and get back under the car to bolt the exhaust hangers back up. Just leave them a little loose for now to help maneuverability.
Step 8: Line the 2 exhaust pipes up and slide the coupler onto them so that its got enough of a bite on either side, and again, loosely tighten them up.
Step 9: Play w/ the exhaust and angles to make sure everything is lined up the way you want it to and then you can tighten up the coupler and the exhaust brackets. You can also slide the exhaust tips on at this stage while you're fiddling with it too. Once the exhaust is about where it needs to be and tightened up you can play with the exhaust tips and get those set and tightened down.
Step 10: Since this system swaps the exhaust valve from the stock drivers side position to the passenger side, the Valvetronic kit also comes with a harness extension so you can route it to the other side of the car. I just pressed it into the heat sheilding and ran that all the way over.
left a bit out for the pic, but that all got tucked in
On the valve side, you wanna tuck it up so it is NOT touching the exhaust pipe like it is in this pic
With all that out of the way, double check and make sure everything is tightened down and lined up to your satisfaction, and thats it!!
And a couple vids for now. Ran outta daylight today to take any more
Valve closed, very stock sounding
Valve open, very not stock sounding
Overall I am VERY happy with this exhaust so far. Only took it for a quick drive as daylight was fading, and with the valve open this has such a nice grumble down low now that doesnt necessarily scream LOOK AT ME! But it will draw attention from those that know. I am still currently on the stock cats/resonators, so thats helping keep things mostly civil. So there you have it. A catback install on an M235i!
That good
Mook ?
Edit 1*
Here's a proper cold start. It's pretty much the same as the stock muffler, except maybe a slightly deeper pitch, but sound level wise its about the same since it starts w/ the valve closed. My neighbors will thank me.
Edit 2**
And here is a driving vid!
Step 1: Raise car off the ground using your preferred method.
Step 2: Make sure your exhaust valve is CLOSED, and then unplug the exhaust valve harness
Step 3: Next comes the fun part. Cutting the exhaust. On many BMWs, there is a little dimple on the pipe that is pretty much an indication for "cut here", but, of course my exhaust did not have the dimple, so I had to work it out myself. I pretty much just laid the new muffler on my chest and slid under the car and tried to work out where I thought the muffler was going to be when it was up on the hangers. Yeah sure this looks about right! LETS CUT!
No going back now
Step 4: Don't have pics, but now you can undo the nuts that hold the exhaust hangers on from each side. Loosen them up a little, then either have a helper hold one side, or brace it with something so you can unbolt the hangers and drop the muffler out.
Yep this is gonna be better
Step 5: Unbolt the 3 bolts that hold the exhaust valve motor on the stock exhaust and remove the motor.
Step 6: If you have OCD, CLEAN the motor
and then swap it over to the new exhaust. The Valvetronic kit comes with 3 new bolts, and a new spring. There is also a metal tray under the motor on the stock setup that you do not need to use on the new exhaust. Make sure the exhaust flap on the new exhaust is fully closed when you position the motor with the new spring and tighten it down. I was a gentleman and firmly held the flap closed w/ my thumb as I tightened down the motor. If there is any play in it, you open yourself up some awful rattling every time you fire the car up. You can also pull the exhaust mounts off the old exhaust and slide them onto the hangers on the new exhaust at this time.
Dont really have pics for the next few steps but,
Step 7: This system also comes with a coupler pipe to marry the 2 exhaust pipes together, so slide that on to one of the pipes, and again, either find a friend to hold one side of the exhaust or find something to hold it up with, and get back under the car to bolt the exhaust hangers back up. Just leave them a little loose for now to help maneuverability.
Step 8: Line the 2 exhaust pipes up and slide the coupler onto them so that its got enough of a bite on either side, and again, loosely tighten them up.
Step 9: Play w/ the exhaust and angles to make sure everything is lined up the way you want it to and then you can tighten up the coupler and the exhaust brackets. You can also slide the exhaust tips on at this stage while you're fiddling with it too. Once the exhaust is about where it needs to be and tightened up you can play with the exhaust tips and get those set and tightened down.
Step 10: Since this system swaps the exhaust valve from the stock drivers side position to the passenger side, the Valvetronic kit also comes with a harness extension so you can route it to the other side of the car. I just pressed it into the heat sheilding and ran that all the way over.
left a bit out for the pic, but that all got tucked in
On the valve side, you wanna tuck it up so it is NOT touching the exhaust pipe like it is in this pic
With all that out of the way, double check and make sure everything is tightened down and lined up to your satisfaction, and thats it!!
And a couple vids for now. Ran outta daylight today to take any more
Valve closed, very stock sounding
Valve open, very not stock sounding
Overall I am VERY happy with this exhaust so far. Only took it for a quick drive as daylight was fading, and with the valve open this has such a nice grumble down low now that doesnt necessarily scream LOOK AT ME! But it will draw attention from those that know. I am still currently on the stock cats/resonators, so thats helping keep things mostly civil. So there you have it. A catback install on an M235i!
That good
Mook ?Edit 1*
Here's a proper cold start. It's pretty much the same as the stock muffler, except maybe a slightly deeper pitch, but sound level wise its about the same since it starts w/ the valve closed. My neighbors will thank me.
Edit 2**
And here is a driving vid!
