Howz550

I had the RPI exhaust for 8 days. Couldn't believe how good it sounded when I started it and took off for the first time. However, after driving it two days, I knew it had to go. The low RPM drone was just too much in the cabin. Just not conducive to having a conversation. And especially annoying if you drive clients around a lot. Sounded like a Chevy Nova with a hole in the muffler. If there was a way to maintain the sound outside of the car and eliminate (or lessen) the cabin noise, I'd probably try another aftermarket exhaust.

AngelSlayer

Last time I talked with RPI, adding the silencer will reduce the volume of the exhaust (both the drone and overall sound) but at the cost of the HP gain. Of course I was talking to him about the M version but I would assume the same applies to their 5 series exhaust. There are probably a lot of options out there for a nice sounding exhaust with no cabin drone (I don't know if Corsa makes an exhaust for the standard 5 series but that's an example of one) but you would not get any or maybe a little of the HP gains RPI provides so I guess it depends on what you're going for. I love the sound of my RPI GT and don't mind the drone too much but I can see how it would be a serious problem if you're driving clients around -- and my neighbors aren't very happy.

r9ndy

Try CC inserts from carchemistry.com it's pretty much the same concept as the RPI silencers, but with the CC inserts you have more disk to choose from.

here's a review of it
http://tl.acurazine.com/forums/showthread.php?t=739889

I bought a pair of these for my quads, they're in transit so i'll probably get these installed this coming wednesday. i'll let you know how to these work out.

melimel

I have the rpi and I have no clue what you guys are hearing, seriously.. the so called "drone" is hardly noticable to me. I mean you can hear the exhaust, but by no means would I ever, ever consider a silencer.. Are you driving in sport all the time? Because this makes your rpm's higher and therefore your exhaust is louder and staying at a higher growl.. (imo) If I want to hear mine more I keep it in sport, but when I dont care whos listening and want to save a tiny drop of gas I keep it normal...

Are you sure your exhaust is broken in? Im just checking....

amit1947

The low pitched drone actually only occurs from 2000 to 3000 rpm. Past 3000 rpm the drone goes away. And yes it's broken in (10k miles).

Bdaddylo

Since you have the V8, you will experience droning below 2,000rpm. Try driving in D with your audio turned down and you'll understand. It becomes louder as your engine strains, so the higher the gear you're in the more pronounced the drone will be. The only way to avoid it is to stay out of the rpm range by driving in DS. Eventually, you'll lose your sense of hearing for that frequency range and the problem is solved.

Rimal310

I have an Ac Schnitzer/REMUS exhaust and you really only hear it at high RPM's. Might be a good alternative also.

RPI sounds amazing though!!! im probably saying that cause i have only heard them while they were driving by

here's a sound clip of the ACS which is actually remus with a $2000 sticker over it.

melimel

ive driven my car every which way possible.. i understand what you MEN are talking about. i just DONT understand why your complaining about it.. Sorry to be blunt, but I dont get it.. Thats all.. I hear it, I know of "it" and honestly to me and my great ears its far from annoying. I just dont understand why some people invest money in an exhaust, then they want to silence it.. It baffles me is all . Nearly all the exhausts on the market have it, and RPI is the only one I know of with proven h.p gains yet people buy RPI and other brands then want to silence them.. ? I dont know, maybe I just have a hard time understanding somethings. This happens to be one of them.. Enjoy fellas

KREED_550i

I had to help my GF this weekend ship a bunch of things. I loaded my car and my cousins SUV. I drove the SUV and it was pure pleasure listening to my car from the outside as well.

Diamond

I have rpi on 07 530 and drone is clearly there for me at anything betwee 2300-2700. Driving at 80mph kept it just at 2700 and it was almost gone. I have found three ways to treat the drone with my experiments

1.do NOT drive in D mode-DS is a must as this will always keep a higher rpm which as the rpms climb up to 2700 the drone gets quiet so higher is better.
2.Shift yourself in manual mode if you have auto and always start in 1st and shift quickly out of the drone rev range

3. The one I cannot explain was my most shocking and nost effective-- Removing the resonator in the middle of the exhaust. The straight pipes after the 2nd cats that is replaced with a smaller 2.5 inch pipe compared to the resonator which is atleast 4 inches in diameter and its a long oval full of holes and a big bend in the middle (I know as i looked inside after took it off). Then after the resonator is 2.75 inch pipe OEM to the rear muffler. With RPI you get 2.5 inch piping, then a stretch of 2.75 inch piping (small foot or so) then resonator which is huge and poor flow.

Therefore my thought is removing resonator and 2.75 inch piping leads to faster velocity gases after the cats which means less droning. Not sure why but same with pipe size. Poeple that run bigger pipes generally have a louder drone.