If I go with a testpipe and have one custom made for the car by a muffler shop, should i have one made without the o2 bunge and wrap the o2 sensor in aluminum foil? I know this works but what will it do the fuel map etc etc? Or should i just go for a bolt on unit with an o2 bunge? thanks. btw this will be connecting a jdm dc header to a usdm length exaust that is around 2.35" thanks

 

I have the jdm header with a test pipe. My test pipe does not have an O2 bung, so I just let the o2 sensor hang and I don't get any cels.

 

are you running a stock ecu?

 

well i was running a usdm itr ecu, but now i have the jdm ecu. Worked fine with both of them.

 

ok thanks, anyone else?

 

I have a modified Godspeed OBD II test pipe with 2.25 inlet and 2.5 outlet. No CEL, 6 months and counting.