S54 Swap Muffler Suggestions

[Staszek]

Technically both. The muffler mounting rubber being backwards moved the through bolt rewards soaking up all the expansion room, looks like it would have to be cut and re welded... BUT..

The mount doesn't look like its in a bind, so it should be "OK" but an exhaust system can easily grow an inch if you're really driving the car.

Thanks I know mounting options were limited we were trying to make sure it lined up right with the Mtech II kit once it was put on.

So far so good but I will keep an eye on it.

[moatilliatta]

Technically both. The muffler mounting rubber being backwards moved the through bolt rewards soaking up all the expansion room, looks like it would have to be cut and re welded... BUT..

The mount doesn't look like its in a bind, so it should be "OK" but an exhaust system can easily grow an inch if you're really driving the car.

[Staszek]

Tech tip, exhaust hangers are backwards, the through bolt should be closer to the front of front for exhaust expansion. If you system wobbles to much you can add the reinforcement that is on the e36 M3.

I really like the E36 exhaust mounts, the factory donuts always seem so troublesome if you don't use the stock exhaust bracket style hanger.

Good to know. So far its been 2 years and the exhaust is solid as a rock. Question and maybe I am not understanding what you wrote, are you talking about the mount location, or that the actual rubber is backwards?

[moatilliatta]

Tech tip, exhaust hangers are backwards, the through bolt should be closer to the front of front for exhaust expansion. If you system wobbles to much you can add the reinforcement that is on the e36 M3.

I really like the E36 exhaust mounts, the factory donuts always seem so troublesome if you don't use the stock exhaust bracket style hanger.

[dude8383]

Bit of an update on my end... I have acquired the Borla center muffler with the integrated x-pipe and now waiting for the Stromung muffler to arrive. Hoping it arrives by the end of the week because I can literally drop it off a few blocks down from RK Tunes to have my buddy weld up the new stuff.

[dude8383]

I did a below to ease alignment when installing the system. When I was welding it all up I knew that with the heat there would be SOME movement so the flexpipe just eases install when the system has to come down.

Think about how the original M20 exhaust systems also had a flex in them on just one bank... I was following the same principal there.

As for the active setup... the E46 M3 stuff doesn't quite fully bolt up to our cars so buying something like only to have to hack it up feels a bit foolish.

[hoveringuy]

1) This is Active Autowerkes equal length exhaust, the idea being that the rear bank is 1 foot closer to the merge so it's lengthened to make it equal.

Thoughts?

Relevance to DOHC e30's?



2) I also see that one of the exhausts pictured above has a expansion bellow and the other one doesn't. Are they necessary?

[Luke_M]

Nice, is yours a dual or a larger single configuration?

Single 3" the entire way

[Staszek]

FWIW I have a borla pro xs in the tunnel area and an equivalent magnaflow muffler in the rear. I really should have used 2 borla's but the point is that it isn't loud at all (for aftermarket) idles nice and quiet, no drone really and it rips when you get on it. I love it and I'm to old for to tolerate noisy drony exhausts. Cheap and nice and light too.

My only complaint is that the borla's don't have a nice exhaust tip but a good shop should be able to make one or attach one I guess.

Yea just change the tips, I cut the tips off the E36 exhaust, had to kick them to the side anyway to mount them due to making sure they lined up right when mounted with the Mtech bumper. Here is a pic of the bumper test fitted with the new tips on the E36 exhaust.

[R3VM3UP]

FWIW I have a borla pro xs in the tunnel area and an equivalent magnaflow muffler in the rear. I really should have used 2 borla's but the point is that it isn't loud at all (for aftermarket) idles nice and quiet, no drone really and it rips when you get on it. I love it and I'm to old for to tolerate noisy drony exhausts. Cheap and nice and light too.

My only complaint is that the borla's don't have a nice exhaust tip but a good shop should be able to make one or attach one I guess.

Nice, is yours a dual or a larger single configuration?

[Luke_M]

FWIW I have a borla pro xs in the tunnel area and an equivalent magnaflow muffler in the rear. I really should have used 2 borla's but the point is that it isn't loud at all (for aftermarket) idles nice and quiet, no drone really and it rips when you get on it. I love it and I'm to old for to tolerate noisy drony exhausts. Cheap and nice and light too.

My only complaint is that the borla's don't have a nice exhaust tip but a good shop should be able to make one or attach one I guess.

[Staszek]

I highly doubt those headers w/ cats would fit.

Doing a Y pipe up front to a 3" the rest of the way back results in a loss of torque, less ground clearance at the rear subframe, and a system more prone to droning. For those reasons I opted to go with a dual system even though it's a lot more work.

Exactly, that's why I wanted to keep it stock diameter's as well.

[dude8383]

I highly doubt those headers w/ cats would fit.

Doing a Y pipe up front to a 3" the rest of the way back results in a loss of torque, less ground clearance at the rear subframe, and a system more prone to droning. For those reasons I opted to go with a dual system even though it's a lot more work.

x2 on this.

Even though I have a 3" y pipe at the subframe the clearance there is definitely crappy. I spoke with Scott at Stromung about whipping up a muffler for me so we'll see how that goes. It's going to be 19" in length and 5x9 suitcase style.

[R3VM3UP]

I highly doubt those headers w/ cats would fit.

Doing a Y pipe up front to a 3" the rest of the way back results in a loss of torque, less ground clearance at the rear subframe, and a system more prone to droning. For those reasons I opted to go with a dual system even though it's a lot more work.

[moatilliatta]

Those who want to keep cats, Is it worth just doing headers with cats in them? Gives your more options for a center muffler

https://www.bimmerworld.com/Exhaust/Headers/aFe-Twisted-Steel-Header-BMW-E46-M3.html?gclid=CjwKCAjw8-78BRA0EiwAFUw8LHn3BrKE2eoe_59wxHx2v54uGPoRBEOwko2WLgmn1DaJv85a9JnbHBoCDPUQAvD_BwE