How to: FREE-FLOW Exhaust without LOUDNESS?

4X4 and Off-Road Vehicles

General 4X4 Discussion

fuma (fuma) 2012-07-23 19:31:55 +0500 #1

How to MAKE a FREE-FLOW Exhaust without GAINING much LOUDNESS.

*FREE FLOW means:
No Catalytic converter
No Resonator
No Muffler
No Flex Pipes

pak786 (pak786) 2012-07-23 19:35:06 +0500 #2

this is the stuff that prevents noise

fuma (fuma) 2012-07-23 19:53:32 +0500 #3

by saying " FREE FLOW " i don't mean " SMOOTH FLOW "

here i mean a STRAIGHT PIPE direct from EXHAUST MANIFOLD
No BEND, No CURVES, Nothing in between
Straight-CUT Input to Output! No process in between.

pak786 (pak786) 2012-07-23 19:55:17 +0500 #4

Yes and that will make noise , i have that in one of my cars and its so noisy i cant use it daily. Neighbours complain too.

And i havent even removed the cat only muffler

fuma (fuma) 2012-07-23 19:57:59 +0500 #5

But HOW to KILL that NOISE ?
is there any method ?

pak786 (pak786) 2012-07-23 20:02:19 +0500 #6

Only way to kill that is with a muffler , but again that beats the purpose of a free flow exhaust

hash4u (hash4u) 2012-07-23 20:42:41 +0500 #7

without resonator and muffler
not possible

Ghuncha (Ghuncha) 2012-07-23 21:14:34 +0500 #8

-put a turbo, it will dampen the noise as a by product

-use a couple of straight through mufflers, increase the diameter of the pipe though it will reduce the scavenging effect and shift the torque bend up the revs generally speaking.

fuma (fuma) 2012-07-24 12:14:23 +0500 #9

@ Ghuncha

Exhaust driven Turbocharger is installed already, it makes a difference in exhaust sound but not that much with straight pipe.
Large diameter increases DEEP Low Frequency BASS, very annoying on streets & people feel shaking+nearby cars , also Turbo Whistle is too loud n clear in straight pipe, looks like a pressure cooker OR a steam engine at MAX boilin' point LOLZ

Charged (Charged) 2012-07-25 06:22:41 +0500 #10

The bass you are talking about is called resonance, go for a smaller diameter like 2 inches if your running 2.5 and 1.5 if you are running 2'', and also a thicker gauge of the pipe like 14 from 16 and so on.

fuma (fuma) 2012-07-25 11:57:18 +0500 #11

@Charged

bro, small diameter is too CRISPY LOUD!! Mid/High-Frequency is increased alot!
instead of this, large diameter is still alot better where Low-Frequency is increased & Mid/High is decreased.

Charged (Charged) 2012-07-26 03:19:02 +0500 #12

Yeah thats true... then you should add a free flow muffler, not one of of those Chinese ones available left right center...go for Magna flow, Borla and the like.
Alternatively, you can study whats inside a free flow muffler and get one made yourself... its no rocket science.