youer not getting much help here bowtie so ill give you my 2 cents worth. we dont use the sniffer here, but my thanking would be that the truck would run ok that away but i dont belive you would get the same sniffer reading on the pipe with the o2 sensor as the pipe without the o2. i think youer going to have to have a o2 sensor in each pipe, but i dont think you can do that with the computor you have. i belive you could get around it with a cross over pipe at the collectors. could be wrong.