That would be expensive, indeed.
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Spoke to dinan in mountainview - still not avail, just taking preorders for now
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I spoke to them yesterday and they will have the 545i exhaust in about a week. So, who's going to be the first in the bay area to get one, so we can hear what it sounds like??!!

 

I've been holding out for the Dinan exhaust but I don't know if I'd pay $1400 for it. At that price, I can opt for the quad Eisenmann or the AC Schnitzer which are both more visually unique than other exhausts on the market.

Anyone know if it's just the rear muffler or is it a bit more than that, maybe including new or removed rear resonators??

 

Just a muffler. It is pricey--when they told me the price I asked if it was a cat back system , but it's just the muffler.

I assume you're aware the Eisenmann quad exhaust isn't a true dual exhaust--the right side is a dummy--see their install instructions, and pic:

eisenmann_install.pdf

 

Yeah, I'm aware that it's not a true quad system but doesn't it look sweeeeet?? I was just thinking the visual appeal might be worth the price.

 

If it were a true dual exhaust, sure. Even visually, not my cup of tea--look inside the tips on the right side--you can see they're not open. But each his own!

 

They're not even opened? I had thought it tapped into the left pipes and had a little flow to it. Hmm...I'll check with soc_fans.

 

Does a "quad" exhaust necessarily have an advantage or is it purely for cosmetic appeal? If someone could please shed more light on this as I don't completely understand the technology.

To my understanding, a car developed with a single-sided exhaust won't necessarily benefit in performance with a dual-side exhaust system. In fact, the increased plumbing may create too much back pressure (as well as increased weight) thereby reducing performance.

In order for a dual-sided system to be beneficial, plumbing must be customized specifically for the car's current engine specs and begin from the exhaust headers and then all the way to the mufflers.

 

I might be wrong here but isn't the stock system somewhat of a "dual-sided" system? It has two pipes and two mufflers although it ends on the same side. I just forgot if the pipes are independent from the head down or if they split off at the cat. So in effect, I don't think the quad systems like the Eisenmann adds more back pressure or more weight than the stock system which already has dual piping. I think the only real difference is that one system has 2 tips while the other has 4 tips.

As to the RD system, the X-pipe that it uses aft of the cat supposedly produces a scavenging effect to suck more air out thereby increasing gas flow.

 

Nope--it's a pure dummy--check the Eisenmann install doc I posted above.

 

The stock exhaust has 2 headers with cats, that connect to 2 resonators, then to a Y pipe, to a single pipe, then split to 2 pipes into the 2 mufflers. With the RD system, you could be affecting back pressure, but I'm sure they account for that in their chipping--not sure if it would be an issue with just installing the exhaust.