Exhaust design for M20 E34

[bazet]

Eventhough E34 is a big sedan, there's very little room for muffler as the tank occupied almost 80% of the space under the rear boot.The original design is something like this pics attached.I'm thinking of eliminating box1 and box 2...and using 6-2-2 layout instead of 6-2-1 in the future.New Layout---------------Header ------> 2 pipes ------> Muffler The pipe size will be the same as the pipe comes out from the stock header.Anyone want to give their opinions ?p/s :Where can I have exhaust header like Zoggee ..and how much ?

 

[kevster30]

Bro,Going with the 6-2-2 is a good idea but you might want to maintain at least one centre box for sound and pressure equalization.If you run on just one rear box, you WILL lose all low end torque on your ride. Trust me..............

 

[bazet]

Ok, what brand of centre box that keep 2 in and 2 out ?..or maybe I can use 525i centre box....My exhaust is bitten by rust..and sooner or later have to change that....What can I gain on 6-2-2 layout instead of 6-2-1 ?

 

[kevster30]

525i centre box would be ideal......or else, get two bullet-shaped mufflers and put them side-by-side!

 

[Tom]

i've tried various ways.. my favourite that i have now is,6(3-1, 3-1) branch extractors -> 2X2"- 1X2.5" -> borla centre -> 1X2.5" -> borla mufflerthere's some lag though... there could be a link between the single pipe conversion now + the unichip map + extractors, power comes in at 4K with a little surge Borla exhaust from the E46 323i, they are pretty loud and raspypipes are all galvanised steel... stainless would be ideal (next project, stainless extractors - downpipes to mufflers, yummy)p/s: i have to say this though, the stock E30 325i centre muffler is a bulletproof great sounding muffler, even without a rear muffler, the 325i sounds REALLY good. i've tried.but please, never ever run without a center muffler. it sounds like SHIT.cheers!Tom

 

[pussy]

Bazet, want louder sound from the exhaust ?if the way i see that you want to eliminate the first box you will loose torque, removing the second box will be bad for the gases as they are not being collected, in other words still resonating...when the gases enters into the final box and emits from your tail pipes, it will sound like your car has cams..the 525 M50B25TU engine has the proper pipes you seek.. remove the cat, insert center bullet empty cock-screw ribbed internal chamber type.. then you will have proper growl..i know somewhere in Bandar Tun Razak workshop has a mid box to rearbox twin pipe set-up for sale. ask ah wai 016-XXX XXXXhave fun..*EDIT: Please do not post up phone numbers. Do so through PM - The Moderator*

 

[bazet]

I have good sound from my existing Sebring....it just I need a clean exhaust layout..nice to see from underneath..not too much restrictor...as the gas need to pumped out as fast as possible.Thanks Tom...will try your setting..