I’ll never forget the first time I was in a dyno cell while testing an engine with 8 oxygen sensors. Instead of just having one or two, which is the norm on most of what we work on around here, each cylinder had it’s own O2 sensor, because data is good. Or is it? It certainly is scary! But why? Well that is because the O2 sensors you are used to watching for info are in fact taking the mixture from 4 cylinders and reading all of them at the same time. That means that one could be lean while the other three are a little rich, and they will even out to where the O2 sensor gives you a good number you like. When you have all 8 cylinders under observation independently, you see the good, the bad and the ugly. And sometimes it really is scary.

Watch how this plays out in Richard’s intake test. He’s testing blow through carbureted intakes on an LS to see how the distribution is between a dual plane and single plane intake. Watch.

Video Description:

DANGER!!! SHOULD YOU TRUST YOUR AIR/FUEL METER? SINGLE PLANE VS DUAL PLANE, WHICH CARBURETED LS INTAKE MANIFOLD WORKS BEST UNDER BOOST? CAN I RUN A BLOW-THROUGH CARB WITH A TURBO? HOW DO I RUN A CARBURETOR ON MY LS? WHICH INTAKE MANIFOLD HAS THE BEST AF DISTRIBUTION UNDER BOOST? IS MY AIR/FUEL METER REALLY ACCURATE? CHECK OUT PART 2 OF THE TESTING ON AIR/FUEL DISTRIBUTION BETWEEN A SINGLE PLANE AND DUAL PLANE INTAKE UNDER BOOST. WHAT HAPPENS WHEN YOU ADD A BLOW-THROUGH CARB? JUST BECAUSE YOUR AIR/FUEL METER SAYS THE TUNE IS OKAY, DOES THAT AVERAGE READING TELL YOU WHAT IS HAPPENING IN EVERY CYLINDER?