Ga16de header/cat relocation

[vegas2.0S]

I Have a B14 200sx. The exhaust manifold on this engine stinks. I want to install headers but doing so will eliminate the CAT. I also want it to be street legal so I'm thinking of moving the Cat to where the first muffler is located, eliminating that muffler and installing a performance muffler in the rear. I'm thinking this should free up a good amount of back pressure.

1) Is there any problems that this would create that I should anticipate? 2) Should install the O2 sensors, in the exact same spots or (i.e. right at the exhaust manifold) or do I just have to get one in front of the CAT and one in back of it?

Any help would be appreciated

[carmo]

I'm not positive, but the way I understand open exhaust is, less restriction is good to a point. Running strait headers to an open four inch dump on a little four cylinder causes problems because there is no restriction to slow the hot exhaust from free flowing past the valves. Thus, the exhaust doesn't have any time to cool down and you end up burning valves.

As far as the 02 sensor. Leave the front one closer to the engine because this sensor directly affects the engines rich lean cycles. and the rear 02 should be after the catalyst. The rear 02 tells the computer if the catalytic converter quit working. And the "first muffler" is a resonator. You could try the exhaust out without it, but if it's too loud for you or your local police officers, try to find a high flow resonator and install it after the cat. and before the muffler. Installing a resonator on my car made all the difference in the world. Goodluck