Exhaust sizes on a stock CT9

[kalibwenm2]

Hey guys,

I'm currently running a stock CT9, on the stock manifold and downpipe, followed by a 2" exhaust pipe to a 3.5" muffler...I have a 2.5" decat downpipe laying around, would it be wise to have it installed with the 2" exhaust, or i should get a 2.5" straight through exhaust pipe all the way to the muffler...? As i've read that this could cause backpressure issues, that might be bad for the poor little CT9...

Thanks in advance...:rockon:

 

[dac69er]

2" is a little small if you have upped the boost and are going to be high boosting alot. otherwise, i wouldnt worry about it, 2" will do fine.

 

[kalibwenm2]

I am running 0.85bar approximately, but planning on raising it up to 1bar soon...

 

[gorganl2000]

if you do upgrade, 2.5" is a nice size which accommodates a lot of power ranges.

 

[kalibwenm2]

but the 2.5" is only for the downpipe, the rest of my current exhaust pipe is 2"...i'm just asking if there will be a bottle neck reaction at the downpipe to midpipe section, due to the difference in size...