Hi,

I kept forgetting to post this, and I can't remember who originally asked but here are the instructions for the Mugen ECU.
I believe the translation picture on the back says for circuit racing this straight pipe type of muffler exacts the biggest gain (in conjunction). Randy1c was the original owner so he might be better informed, and maybe can read kanji better than I.

-m

 

I have the Mugen ECU with the BYS straight pipe... (and SC too I might add). Maybe that's why low - midrange power is accentuated so much with my Mugen compared to my stock ECU (but at low rpm the presence of a cat should have zero impact and little air-flow resistance)...


Who knows...

 

Wow! is that red sealing wax in the corner (really important JDM document) or did you kid leave his gum in the wrong place (not so important US document?