Technical How come?

[Alex22]

How come my mates sei (JR) sounds much more amazing than my cinq? when

He has a peco cat back and i have a janspeed cat back (which we have decided are practically identical)
But he has a supersprint 4-2-1 de-cat manifold on his mpi, and my spi cinq has a janspeed 4-1 de-cat manifold.

The difference in sound is lots!!!!>>>> would that just be the manifold?? or because my de-cat section is partially silenced?

confused.com

 

[rallycinq]

I presume you haven't cut the silencers open to check that they are identical. There are many ways to construct a silencer and unless you are desperate or daft enough to slice the things open and have a look I think you will have to accept that the construction is different leading to different volumes of sound.

cheers

D

 

[Alex22]

Yer, i think i'll just buy a sei

 

[JonnyBoy]

If your de-cat section is silenced and your mate's isn't then that makes a hell of a difference. On my Punto, the exhaust was very quiet with the cat but it makes a fairly loud metallic sound with the de-cat; I think this is because my de-cat is just a straight piece of pipe so the gases go straight into the expansion box, whereas the cat acts as a sort of primary expansion chamber which absorbs some of the sound energy in the gas.
That's my home-brewed theory, anyway!

 

[Alex22]

yer his de-cat is just a piece of pipe lol, whereas mines a sound deadening one