I have ordered the resonator-straight pipe from MG Racing to complement my Mugen headers (on order) and aftermarket exhaust for more free flowing exhaust... I hope that it helps.

Will I see a "check engine" light on due to the lack of catalyst?

Thanks!

 

OK, for those of you that are polluting the earth in search of more horsepower, you owe the rest of us a before and after dyno. And I don't mean a Pinky's seat-of-the-pants dyno

 

Shaner-

Yes. Unless you use a competition ECM that eliminates the catalyst O2 sensor.

-Nick

 

I'm getting the BYS pipe from 1RandyC, I wonder if he had the engine light go on...

 

I

 

mingster and others who are contemplating on removing catalytic converter please pay attention to this warning!
I certainly gained something by using the BYS straight pipe in place of the catalytic converter.
However........
Two days ago I removed the Mugen ECU and replaced it with stock ECU. The car immediately felt loss of power and vtec didn't engage at all. I thought it was FPR and I fooled around a little bit. As the day go by the car started to run poorly with some hesitations and yesterday on the way from work I got the check engine light.
And today I replaced all the exaust system with stock system as well as the catalytic converter in place.
I still have to go to Honda dealer to reset the trouble code since simple ecu reset will not clear the check engine light but the car is now running better.
I will not run hard as of yet until if the check engine light is indeed for sure induced by removing the cat, but I am sure it is.
So, if you do not have performance ECU like Mugen this upgrade is out of the question.
I will give you guys more update, so....

 

Thanks for the "heads up". How did you try to reset the code? By removing fuse #5 (I think it is) a little while while the car was off?

 

1RandyC,

How much was the Mugen ECU and where did you get it from? So, if I am getting the cat replacement pipe from MG Racing then I should get the ECU? What else will the ECU offer me with my oter upgrades (supercharger, headers, exhaust, bored throttle body, honed/polished intake manifold)?

I figured loosing the cat would let my exhaust from the forced induction exit easier...

Thanks!

 

Let

 

You could keep the stock ECU, just figure out what voltage the stock ECU wants to see out of the second o2 sensor, and replace the sensor w/ a resistor.

Then just plug the hole in the BYS pipe.