I'm thinking of going for a turbo back system from BCS powervalve, the 200 cell powervalve prestige version. Presently I'm running a Cobrasport downpipe with a 200 cell cat with the OEM catback, and a JB4, using a HJS mini cat (900 cell) to keep the CEL at bay. The location for the sensor is downstream from the 200 cell sports cat with the Cobrasport downpipe. I have a need to keep the CEL off without the JB4 connected/using future use D, as in Northern Ireland our MOT tests are done in a government testing centre and nothing can be connected to the OBDII port. The gas test should be fine with a 200 cell sports cat, it's just that it looks like on the powervalve system that they expect you to map out the second sensor with a stage 2 tune. The sensor location looks to be pre-cat, from the images I can see online. My guess is this would equate to similar gasses conditions to a decat downpipe? I'm basically trying to find out if anyone is running the turboback powervalve exhaust with a JB4 & mini cat with no CEL, or even just anyone running a decat, JB4 and using a mini cat to keep the cell at bay successfully, without the need for future use D? I'm guessing this is a bit of a long shot, but thanks in advance for any help.