I recently pass emissions on my turbocharge GSR and wanted to do a few things to it. I wanted to do a 3inch downpipe and exhaust for my car but I heard that the 2nd O2 sensor in the back, you can't remove it and if I cut it the CEL will go on (it's a 96GSR ODB2). Someone told me the change the ECU back to OBD1 and I won't have to worry about that 2nd O2 sensor. What do you guys think? I have a budget of about $1500-$2000 to spend on new stuff.
Here's my list

MSD 6A $300+$220 for install
3inch downpipe +exhuast $600
Manual boost controller XS $60
Timing belt+alternator belt+water pump $375
a clutch job if there's any money left.

Already on car.
DSM 450cc injectors
VAFC
MSD BTM
adjustable FPR
walbro 255llp pump
Turbo timer
it's currently making 210whp 166wtq at 6psi
I want to boost it to 8psi
What do you guys think I needed for the car?
plant to rebuilt it next summer.

 

i would get a good fuel management like hondata, but you would have to switch to obd1 and all you have to get to do that is the obd2a obd1 jumper harness and a obd1 ecu and thats it, then you wont even have to worry about that seccond o2 sensor

 

Removing your catalytic converter and converting to 3 inch exhaust.

This will make it so your o2 sensors if they are still in the new 3" exhaust piping will throw a cel. There is too much o2 for the second o2 sensor.
You are correct, an obd1 ecu only uses the front o2 sensor. That wont work for smog time though.

 

I have Hondata s200 right with a Obd 1 conversion harness right but I still throw a check enjine light...... dunno? I have afull 3 inc exhaust also and test pipe??? Any idea as to why I am still throwing a cel?

 

if you just dont want a cell i think you can just get a o2 simulator

 

you need to figure out what code your pulling. Your not throwing a code for the o2 sensor.