This is because when we're looking at an air fuel ratio, let's say for example our stoichiometric air fuel ratio of 14.7:1, that is simply a mass ratio. 05:43 We're talking about 14.7 parts of air to one part of fuel, let's say we're talking in grams, 14.7 grams of air flow into the engine versus one gram of fuel being supplied from our injectors. This is why a wideband air fuel ratio gauge is such a must-have for carburetor tuners. Unlike a narrowband air fuel ratio gauge, the wideband air/fuel ratio I've never worked with a Turbo engine, but from what I've read on this site, trying to tune a turbo with a NB - especially with smaller injectors - is a recipe for a slagged engine! Simply changing the injector size in the req-fuel calculated will do a lot of the work, but you'll still need to get the dead time right for a good idle and mid-range. how to tune holley terminator x for beginners // target air fuel ratio - Holley EFIi figured this video would be 10 minutes long, but as usual i couldn't sh Option 2 - Disable NN and use Volumetric Efficiency Tables (VE): From the few I have seen the factory VE tables need a lot of work. Cold start tables also need work. a - set desired AFR. b - disable baro learn (has been said to be a complete multiplier for tune and may cause uncontrollable swings) 4. Set the idle mixture to the highest vacuum reading by using a vacuum gauge connected to the constant-vacuum port of the carburetor’s base plate. Slowly adjust the first idle-mixture screw. Make one adjustment only to the first screw. The adjustment should be no more than an eighth or quarter turn. “The beauty of this method is that once the engine is tuned and the VE table is correct, you tune it by changing air/fuel ratio and not the VE table if you are trying to lean out the cruising air/fuel ratio from 14.0:1 to 15.0:1,” explains Flynn. The proper fuel injectors work in conjunction with the turbocharger to create the perfect air-fuel ratio, allowing the engine to achieve maximum performance. Fuel Pressure. Fuel pressure is simply known as the pressure in the fuel system being generated by the flow dictated by the fuel pump. This may have been posted about before, but I have a question. I just put the JLT Super Big Air Cold Air Intake on my 2014 GT 500 and installed a BAMA custom tune. What should the Air/Fuel Ratio be running at idle and how does that compare to a stock set up? The gauge on the car is showing 13.8 to 14 at idle. Thanks a lot. The goal of racing engine tuning is to generate the best power for your setup. Knowing the limits of your vehicle—and tuning within those boundaries—ensures racing success. By maintaining a good air/fuel ratio when air density is fluctuating, among other controls, you keep your engine operating in top form. viZit.