Eta-to-M50: Build thread

[Jand3rson]

Evening the guy at the exhaust shop recommended the Dynomax, before I even mentioned it. He just said to make sure it's the chambered one, and said it would tone the noise down a ton and probably take away most of if not all of the rasp.

Raspy on an M50 sounds kind of sweet. Its not a daily driver, why care?

I don't mind a little rasp, but the whole system overall is super loud, and just doesn't sound good.

[MR 325]

Well, then what I'm going to do for now is order the Dynomax super turbo, a single 3" in/dual out is only $65. Everything i've find online says they're super quiet and will do wonders for loudness on pretty much any exhaust system. The flowmaster doesn't eveeven seem like it has packing, mostly just baffles.

Flowmaster mufflers are chambered. They don't have packing.

[MR 325]

Evening the guy at the exhaust shop recommended the Dynomax, before I even mentioned it. He just said to make sure it's the chambered one, and said it would tone the noise down a ton and probably take away most of if not all of the rasp.

I remember we ran one of those on a customer's M50 car. It was ebay headers, full single 2.5" exhaust, single cat, and the Dynomax. Super quiet and nice to drive. Yours should sound perfect since it has the Magnaflow in place of a cat.

[Jand3rson]

Nice. I'm going to get the 22" one, too. The 13" seems like it will be too short to do much good. What was the rasp like?

[LJ851]

Nice. I'm going to get the 22" one, too. The 13" seems like it will be too short to do much good. What was the rasp like?

All the Dynomax mufflers are very effective, they are not at all like a straight through. 22" inches should be very subdued, a grown man's muffler.

[dannyb]

any specific dynomax model or any will do?

[bubbajan21]

Are these E28 M5 rubber mounts?

[shiboujin]

Look like stock GR260 ones to me

[Wh33lhop]

Those are regular E30 trans mounts with Mike's trans brace (should have been pink). The E28 mounts people use for 24V swaps are motor mounts, not trans mounts.

[bubbajan21]

In the "DOHC Swap Basics" sticky, it lists "E28 m5 or two 320i trans mounts/ which are cheaper." So do I just use stock E30 trans mounts?

[shiboujin]

E21 trans mounts are stiffer than the stock E30 ones. But both will work.

[Jand3rson]

Those are regular E30 trans mounts with Mike's trans brace (should have been pink). The E28 mounts people use for 24V swaps are motor mounts, not trans mounts.

Yep, those are stock rubber E30 trans mounts, and my motor mounts are E28 535i green mounts.

I was going to go urethane tranny mounts, but that pair was basically new. When the time comes to replace them, I'll probably go urethane, along with the motor mounts.

Ordering the new muffler tomorrow, but I'm still trying to decide if I should get the 13" Dynomax or the 22". After driving the car a bit today, all of the loudness that is really bothering me the most is up high and at WOT, at idle it really doesn't sound terrible, it's just too loud. There's only a $10 difference, but it's also a 9" difference, and I'm worried he's going to have to totally rework the piping going back to the muffler to make it fit, and make the tips come out right.

[bubbajan21]

I've seen all kinds of stuff with motor mounts, 2 green, 2 black, upside down mounting, etc. What is the best way to do it? 2 green? Do you know why 2 green is better than the stock e28 m5 1 green 1 black set-up?

[Jand3rson]

I just went with what Blunt recommended, he said he'd used the 535i green mounts on all his swap cars.

[AndrewBird]

I'm worried he's going to have to totally rework the piping going back to the muffler to make it fit, and make the tips come out right.

The only "reworking" he would have to do is cut the pipe back a bit farther. I would be more worried about the muffler fitting under the car more then anything. Might want to measure the area where the muffler goes to see if it will fit ok.