Exhaust System: Mugen Twin Loop

[zhaf_b16]

Hi guys. What's up? Just bought the Mugen Twin Loop exhaust system (piping from DC2, muffler from EK9) recently but still don't have the time to install it. Anybody use the same exhaust system? What I want to know is why the piping size is not the same from front to rear? It is like 2.2 inch from extractor to center bullet. From center bullet to muffler flange it gets bigger to 2.3 inch. From muffler flange to muffler it gets back smaller to 2.2 inch. Please take note that I only estimate the size because I don't really check. Others who also use the same sytem, I highly appreciate if you can comment on it.

 

[skye_n1]

B18C originally comes with 2.3" piping, u'll find some is with 2.2" because in japan they simply change the broken/corroded pipes to complete the car.

twinloop for B16B is with 2" piping, B18C 2.3" piping.
You'll notice there slightly drop in torque if u put twinloop from 18C to 16B (which means slower pick-up and higher fuel consumption) but u'll get higher top speed.
Correct me if I'm wrong.

 

[zhaf_b16]

do you mean that for b18c the original mugen twin loop piping size from front to back is 2.3 inch? does this mean that mine has already been modified/mixed between b16b/b18c?