E55 RUSS

We need to hear this BEAST ...Post a clip

medici78

I think paying $2500 street price for a pair of mufflers is ridiculous, which is why I never considered it on my M3. Its technically a cat-back b/c it goes behind the SECONDARY cats, but because of this i dont consider it such. If anything, I'd say real (though likely still minor) power gains are to be had by removing the secondary cat, though nobody can confirm at this time. FI cars need as free-flowing an exhaust as possible, and I have a feeling the E55 is no exception. I will be talking to a local fabricator shortly to see if he can do this to my car. However, removing this stuff and adding the Eisenmann would probably sound ridiculously mean...which is cool w/ me. :v
Can't wait to hear Rev it Up's car. Maybe I would be convinced to pay a ridiculous chunk of change if it sounds good enough. However, I wonder if a custom made exhaust using, say, Magnaflow mufflers wouldn't sound as mean. I would probably order all the bends and have a fabricator do the work, and still spend less than 1/2 what the Eisenmann would cost. Makes you wonder if most of the high end exhausts prices are all just based on marketing.

E55 RUSS

I suggest you remove secondary cats and put bigger diameter X-pipe and good muffler and this wou;d be nice exhaust...remiving one set of Cats and X-pipe would definately give Nice sound and at least 10HP...

My friend just removed Cats on his M5 and leaved the rest on the exhaust stock and he gained Dyno showed 416 HP, whereas reg M5 should have 400 HP (taking european numbers)...


One thing I was told that those first set of CATs which people call here primary cats...Were called by MKB as pre-catalytic converters...so this means secondary CATs are the Main ones...but not sure about this???

Anyone know if they are the same... and if you'll remove you Cats make sure you leave ) 2 sensors in place, so you car wont detect any faults..

medici78

You pose a good question. I've heard some people here say they removed their "secondary" cats, which i understand to be the rearmost cats, but I know kleeman removes the "primary" cats when installing their headers..

vraa

Are you guys looking for performance or the noise?
If the latter, try just removing resonators?

E55 RUSS

Performance of course...Yes Kleemann removes Primary Cats when installing thier headers....But I dont understand why MKB called them PRE-CATALYTIC converters...May be they are not the main CATS...Are they the same as Secondary Ones??? Anyone

I am thinking of removing all 4 CATS here but in US you wont pass Emmision tests...

The problem that I've had with my M5, the car would throw black smoke out of the exhausts cause it runned rich, since O2 sensors got more outflow (more air) and mixed more fuel...Anyone knows this staff... I am right???

So the car runned rich...Eventhough the car went at bit faster but I dont like the idea of E55 throwing black smoke out of 4 nice exgausts like OLD car...

Hilsmann said that he removed Secondary CATs and put X-pipe and still passed emmision test...and gained power...and no smoke...

BenzoBoi

^^That's what I did ...

I took out my resonators and put a borla race muffler on there. Sounds pretty decent. Have yet to get on a dyno...maybe sometime soon

JamE55

Just soiled my pants after hearing that clip! :p Damn that isht is sick!