cat bypass question
 

If you were going to use a cat bypass, does the construction material make any performance difference at all. I would not think so, but thought I would ask anyway. Maybe I am missing something. I know longevity would be better with a SS, but cost for replacing the steel one might be worth it over the long run.

something else to consider is the exact type you want. Do you just want a bypass or a euro style pre-muffler with an expansion chamber. The straight pipe style give a nice note change but little if any performance, while the pre-muffler expansion chamber style will give you both, from what I have read.
BTW...There is a nice euro ss premuffler available in the classified section. seller is archnraft and the thread is about an 85 Euro car being parted out. You will have to have an O2 sensor bung welded in but it is both easy and cheap. I believe it is an 18mm nut that you need to weld on.

Yeah I now... Anna and I are talking. Thanks

I am confused...
 

Bought Anna's premuffler. Anxious to install with my M&K, but still a little confused about the whole O2 sensor deal. I undertand why they are typically needed. From what I have read on the list here recently from searching, the O2 sensor was definitely needed on Carrera's that due to the DME. But I have an 83 with mostly stock 3.0 CIS. Can the O2 sensor be simply left unused or not? This is where I am not totally clear on the subject. If I need it, then I will weld on a bung and go with it. Otherwise, any benefits either way to leaving it off.

Thanks

bump up for an answer.

Not as familiar with SC's. I understand the SC and Carrera can be run without the O2 sensor, but not sure what adjustments need to be done to compensate.

Re: I am confused...
 

You want the O2 sensor. Motor will run smoother and at proper mixture.