SoCalM5Mang

Hi Guys!

I've been searching these forums for a 3 weeks now. There is a lot of info to digest on going Quad with custom set-ups versus Dual bolt ons. I'm extremely grateful to everybody here who has responded to my questions.

I've debated doing an upgrade on my currrent Dual stock system with either:

(Remus $800(P&I) or AC Schnitzer $1400(P&I) but am now contemplating going quad because it definitely looks more agressive and balanced.

My biggest concerns as many of you know is a distinct Euro Growl(minimal droning and resonance) and most importantly minimal to no loss of Torque.

I don't want to pay $3k+ for a RD Sport/Hamaan/et al Quad.

I'd like to keep my budget at $2k(or significantly under)and get a custom and high quality Quad Exhaust, with 2 Mufflers and an X-Pipe.

What do you guys think is the best option?

I understand it's very hard to customize a Quad set up on a 550 due to the Battery compartment. If you think it's not worth gerry rigging piping and a muffler for cosmetic reasons, tell me and I'll just improve with a Dual as quoted above.

I'm looking for BEST OPTION Quad solutions guys.

From speaking with Roddy and Newbie Bimmer, the Remus Quad for the 530 "might" be an option fitting my parameters.

Thoughts?

So Cal

CampioniShop

You want:
Euro growl
No resonance
No Power loss
Not too expensive

Remus quad:
euro growl
no resonance
no power loss
not too expensive

Bimmer32

First off, you'll need a quad exhaust bumper. That set aside, what do you mean by a Euro Growl - a raspy higher pitch growl?

Since the battery compartment is the challenge, let's tackle that muffler. I think you can get aftermarket turbo mufflers that have center/side offset or side to same side offset in sizes of 4 x 9 (not larger). Keep in mind:

1. Turbo mufflers will be significantly quieter and therefore eliminate the droning/resonance compared to the universal straight through mufflers.

2. The larger the muffler size, the better sound dampening (maybe between 2-3 db for a round 4" vs. 4x9 oval).

3. Keep all 3 OE resonators and add an x-pipe for balance. Yes there is room.

4. Do what Ramus does and spend less money by adding a transverse muffler on the left, connect the OE butterfly valve to the pipe running to the right side.

5. With any straight through system (unless you change out headers and cats), there will be some growling/droning/resonance when you hang around 1500-2100 rpm on a v8. Some more some less. Turbo mufflers (baffled or OE) is your friend when it comes to drone free below 2000 rpm on v8. I like Dynomax turbo flow director technology.

6. Once the muffler decision has been made, then you will start thinking about exhaust tips. Straight, angle cut, size, staggered? Note, I have search and have not found staggered dual tips. You'll have to buy 4 or custom made.

7. The best advice is, if you see a setup in person and heard/hung around 1500-2100 rpm, and you like it, get it. Otherwise, sound is very a relative and personal taste.

Good luck and ask lots of questions.

CampioniShop

With the turbo mufflers, restriction will imply, you will have power/torque loss.
Our exhausts are straight through, yes, but as shown by Newbie Bimmer, they are still VERY quiet and drone free.

Bimmer32

Not true. The limited restriction (loosely used) of turbo mufflers like dynomax turbo will actually help with the scavenging effects and helps with low end torque. I wouldn't be surprise if the OE mufflers are turbo charactered (chambered, tube, baffled). Opening it up would not gain any low end torque, but only at the high end HP. That's why BMW added a butterfly valve to the second muffler, created a sort of side resonator out of the second muffler when the butterfly valve is closed.

As for sound, I'd like to hear it hanging around 1500-2100 rpm since must street accelerations will restrict the v8 rpm at that level. Mufflers with the Helmmoltz chamber is the best solution for quiet sound. Some turbo mufflers are better designed than others with regards to air flow.

CampioniShop

Straight through design is the ultimate in terms of performance, and levels of resonance can be controlled with a properly designed core and packaging.
If you want a quiet sound, then don't change the exhaust at all, I don't get it?
You are proposing to change out the OE mufflers for basically the same chambered design only with a different brand name.
No sound increase will occur, no performance gain will occur. I don't understand the point.

Bimmer32

There is a slight or greater increase in sound with aftermarket turbo mufflers compared to OE because of the lesser restriction with aftermarket. OE's goal to have the most quiet sound. Hence, replacing an OE muffler with aftermarket will increase the sound level. You said that Remus is "very quiet." Please help us decide with a sound clip as requested. Sound can be captured very effectively with a 1 or 2 years old stereo equiped camcorder costing about less than $400 dollars.

I wished exhaust manufacturers advertise not only dyno chart but also db levels at the rpm rainbow and a sound clip with typical engine cylinders. That way, the customer will have a greater view of what exactly they are paying for. Additionally, the dyno charts posted are somewhat a joke because it's not even in the double digit and worser, 5-10 HP increase means nothing in the streets, not to mention for a 325-360 HP engine.

The other reason to go aftermarket is to achieve the quad setup as the originator noted.

CampioniShop

Sound clips are available, info@remusexhaustshop.com

Bimmer32

Please post it to this forum or on your website. I'd and other qua sideliners would love to hear it.

I don't know about the 6 cyclinders, but the 8s' drone/resonance/loudest is between 1500-2100 rpm acceleration or deceleration. Anything outside that range is music to even the most conservative or racing ears.

SoCalM5Mang

Here is what Matt sent me previously.

Stock of 550i and Remus Dual Installed