I recall someone saying that there were issues from running an open header/open cat?

I want to know, if it is bad to run your car like this, what happens and why does it happen.



TIA

 

1) Well unless you have EMS, you'll be throwing a code for your secondary O2 sensor for one
2) It's highly illegal
3) Noise
4) Smell

As far as performance goes; #1 is all you'd have to worry about

 

*I didn't see your edit
I understand the smells,codes,legal issue
So there are no unsafe issues? I remember reading somewhere that it was unsafe or it would hurt performance.. guess I'm wrong.

Just tried to clear a thought.

 

you will lose performance with a loss in torque, you need approximately 3 feet of exhaust pipe from the end of a header to maintain torque in the power band.

 

^thanks & if you dont mine me asking, where was it found to be 3 ft?

 

Uhm, car might run lean as well.

 

Open Header with a test pipe would be good enough.

 

You have proof of this? Open header has been proven to make the most power time and time again. Check out the All Motor section on HT.

EDIT Actually on an S2k this might be different. All of the headers I've saw have a very short collector so it'll bolt to the OEM cat. If you do decide to run open header, you might think about bolting different length pipes to the header, to get the optimum collector length.

 

A header and short piece of exhaust (proper length and diameter on both) helps scavenge the exhaust from the cylinders therefor more air goes in on the intake stroke.

 

The scavenging takes place in the collector, which is part of the header itself. The collector is actually the most important part of the header; length, diameter, taper are all factors. Everything after that is useless as far as power is concerned.