Ripped Out Centre Muffler

[robtek]

Hey guys,

Had an engine rattle for a while now, thought it was a pulley, then mechanic said it was centre muffler, I've blown cats before but this time was different, so took the car to muffler joint, turned out the rattle was from exhaust heat shield cat back, so just ripped off the heat shield from cat back

While I was there and already keen, ripped out the centre muffler and replaced with twin 2.25" pipes, goes a little better, and sounds a bit better than stock

Anyone else done this?

I know its not a full exhaust system but have mortgage and Thailand coming up so not doing mods for a while Used to have 3" twin, pacemakers, high flow cats, straight through mufflers on my old supercharged VTS but kept getting EPA fines and noise test notices, pissed me off

[Bellato]

Yea I think theres about 50 of us that have done centre or rear muffler delete..

[robtek]

Anyone who did it, do you know if the centre muffler removal actually made rwKW difference on the dyno??.,...

CURIOUS lol..

[freeze_dk]

More noise then power

[robtek]

thanks mate, yeah thought so just wanted to make sure, you never know lol, 1rwKW ..

[Kroozin]

from what I've read the centre muffler is supposed to be the most restrictive (disregarding the cat) vs the rear the muffler. People are getting away with cat back systems and not needing a retune though as the cat is what really determines the flow to a point.

[bcl]

From my notes from 2003 mods.
There are a number of exhaust components post turbo in the standard car, as follows:
· A single dump pipe off the turbo. There is no splitter inside this attempting to separate mainstream gas from wastegate gas, and probably not required until much higher power levels (I mention this as it is a common mod on rexes)
· A 3” down pipe to the cat
· A restrictive cat with typical internal honeycomb pattern; 3” inlet with and dual outlet 2.25”
· Dual 2.25” pipe to the center section
· A center section of dual 2.25” pipe to the center muffler then continued dual 2.25” pipe to just near the rear axle. The center muffler is of straight through design, but is quite effective in reducing noise
· A rear section of dual 2.25” pipe which goes into the rear muffler, but the pipe reduces to around dual 2” through the muffler, thereby causing a “daming” effect on gas flow if you want big power.

First exhaust mod in 2003 was remove the centre muffler, so done 10 years ago.... then the flood started.
Brian

[Bellato]

Wikipellor reckons rear muffler delete will give gains for what it's worth.

I don't think there would be many that would be willing to get a retune on just a muffler delete. Feel free to be the first

[old_mate]

My car made within 2rwkw with and without the centre muffler

The sound it made without it was terrible