Well I wanted more sound and the intake mod was not cutting it. I have the RPI exhaust on my 07 530 with 258 horsepower factory;.

The RPI pipe is 2.5 inches compared to the 2.75 inch stock pipe that goes from the resonator to the rear muffler. I removed my middle resonator today and the y-pipe--had them fab a new y-pipe and ran 1 2.5 SS inch pipe all the way to the RPI exhaust piping which met up perfectly since they were both 2.5 inches. Had them welded together. So now from headers--it goes headers, primary cats, secondary cats--2 pipes 2 inches each that enter into a y pipe-y pip distributes into the 2.5inch single pipe and that conntects to the RPI single 2.5 inche pipe.

Sounds REALLY good. NOt as loud as I thought it would be, not overly raspy, just as if you took the rpi exhaust sound and multiplied it by 2 or so. Maybe not that much but a nice 1.5 times louder at every frequency than the rpi but maintains the rpi type of sound.

Surprisingly that is NO drone-it took away the drone of the RPI with resonnator. My thought is if you look at the resonator, it is all wed and wierd hollowed shaped that is perfororated. The straight 2.5 inch pipe lets the exhaust gas run through quick and fast. My guess is the odd baffle shaped resonator created the drone by slowing down the gases at that point.

SO if you want even better rpi sound, no drone and a 60 dollar mod PLUS another 30 pound weight savings its great.

All in all I saved 30 pounds from the RPI rear muffler and now 30 pounds from the resonator delete. 60 more pounds shed off the 530==I am approaching 3400 pound unladen based off bmwusa.com when it was up and subtracting all the weight I dropped, including rotating weigght of tires and wheels which cannot even be compared since rotated weight is a totally different ball game.

 

Hi Diamond,

Before you removed the resonator, how was the interior noise levels?

 

Lets hear it. Make a video. I have a 530 with magnaflow and resonator delete as well. Sounds much louder, deeper, and more defined.

P.S. - You're still an idiot. But post a video anyways.

 

every RPI sound thread without video = Epic Fail!

 

you cant pick up sound subtlties over a computer so its a total waste to waste money with videos,

I can say the drone is slightly better and the overall sound characterstic is the same, only amplified. Notice down low grunt as well with maybe a touch of loss of top end pull which which meakes sense using smaller diameter pipe than stock 2.75.

I like it a lot thought-

by the way both of you are idioits and you still read my threads now who OWNs you

 

So much FAIL in here. Dude u dont even have an E60, u probably roll a corolla. Theres plenty of vids on here where we can hear an exhaust sound just fine. ie brabus tunnel vid. U are an EPIC FAIL whats your excuse for not even posting a pic? Uh uh it sounds lower like rrrraarrrr as oppesed to grrrrarrrarrr u know?! So lame! SMFH

 

Have you thought of removing your cats?

 

dont read the threads than guys-this is for people interested or thinking about doing this mod.

No place here will remove cats and no would I want to-for the few extra power not worth it and failing emissions.

I have enjoyed the change to 2.5 piping straight back to the secondary cat. So out of the secondary cat there are 2 2inch pipes about a foot long before entering the resontator via a ypipe, and out th eresontator comes a 2.75 diamater STOCK pipe.

With the RPI-the rpi has a 2.5 inch piping that meets up to the 2.75 diameter piping. and still keeps the resonator which is NOT straight through. It is this huge baffled chamber definetly for noise reduction. It is a large voluminous space.

Our e60, atleast the 530 has an absolutely perfect exhaust-it is almost exactly straight back with minimal bends or curves. I now have 2.5 inch pipe from the secondary cat fitted with a ypipe all the way to the rpi muffler which is now welded to the rip muffler. I also was able to do a softer mandrel bend with the fitted new pipe since I could get the resonator out of the way. It is a very soft virtually straight pipe from the downpipes/cats to the exhaust tips-

I notice a HUGE low end gain which is perfect for the n52 car which really lacks the low end punch. mid range is the same and top end is also a nice improvement in flow.

I think the stable increase velocity with the smaller piping all the way through instead of RPI which is only 2.5 inch piing for a very small part of it--gives a very consistent evacuation of gases.

Sound wise it sounds just like a louder version of the RPI alone-maybe 1.5 times louder--sounds great and same amount of drone.

great mod

 

I knew this douchebag didn't even own one. I KNEW IT. This fucking thread proves it.

 

ive been thinking of doing this mod for a bit now