Performance, same or maybe slightly better. Mileage, probably no
significant change. For emissions, your NOx and carbon monoxide output
will go way up. Generally you won't see any significant improvement in
power when removing the cat unless you also do something that NEEDS
the extra flow, like porting or bigger valves.

On 7/18/05, Christopher Gronski <gronski@gmail.com> wrote:
> This is an poitically incorrect question but I am going to ask it
> anyway. What happens if you run your vehicle without a catalytic
> converter installed? Assuming you had a bypass tube installed would
> you just install your exhaust sensor there? What would the effect on
> performance and mileage be? How much would your emissions go up?
> 
> Thanks,
> Chris
>