vortexx

Hi Guys,

I just had my Catalytic converter replaced on my 00 Si since it was throwing code 67 and was partially melted. The engine is completely stock, aside from an intake and 135k miles of some fairly spirited driving. I went to save some money and had my local small honda specialist install a 3rd party non-oem Cat.

Before I had the Cat replaced, I had the usual B16 ridiculous (and awesome) wail from the intake at vtec engagement, from 5500-6200, and then it would quiet down a little, and then get loud again right around 8100.

Well now, after the non-oem cat is on there, the noise around 5500-6200 is barely noticeable compared to with the oem cat, and it only really gets properly loud around 8100rpm. Now the VTEC engagement area from 5500-6200 sounds quieter than the car did with the stock intake!!! What the #$(#???

The only explanation I can think of is that there is greater backpressure from the new Cat, however I have owned the car since it had 7 miles on it, and I got the intake on there after a year of owning it, and the car always had this awesome wail at vtec engagement, and now it doesnt

As if revving to 5500 didnt take up enough roadway, now I have to rev to redline to get the noise! Ack! If i knew that going with a non-oem cat could have changed my intake sound, i woulda paid the extra few hundred for the oe part.

Does anyone have any ideas what happened to my lovely vtec sound?

Thanks

vortexx

Anyone have any ideas or suggestions? Thx

Jdmeg2kid

It's just a sound, get over it.

hatchy96

Does the exhaust sound any different? I'm not sure that there would be that big of a difference in back pressure from just a non-oem cat. Did you notice it right after the install of the new cat?

slvrcvc93

Well since there is more restriction on the exhaust pressure, I'm only assuming the engine has advanced or retarded its timing to better suit its use and giving you better gas mileage.

vortexx

I cant say whether the exhaust sounds any different, cause I cant hear it over the intake (stock exhaust). I noticed it immediately after the install of the new cat.