<strong>2:45 p.m.:</strong> The system uses a single wide band oxygen sensor. Welding the bung into the exhaust pipe is one of the things you may want to do in advance to make it easier to complete the EFI swap in one day. You can install this in either bank of a V-6 or V-8 engine. The ideal location is 2-4 inches past the header collector. Don’t install it in the outside of a bend which would give a false air/fuel ratio reading. The advancements in oxygen sensor technology is one of the keys to modern EFI systems that can quickly and accurately self-tune to keep the engine at the desired air/fuel ratio.