I am on the edge of my seat hoping that you learn something new about gaining significant performance gains with one of these tractor engines (essentially).
I do have some serious concerns about going with dual injectors though. It seems that would compound the effort to tune this setup by a factor of 2 if not more.
Can the 2 injectors be adjusted separately?
Each adds mix to all cylinders, but the intakes are grouped differently: left FI serves 1-2 and 3, right FI serves 4 and 5-6, but the exhaust grouping separates 1-2-3 and 4-5-6 completely. Reading each manifold will give you data from all cylinders because of the plenum.
How will it do cylinder to cylinder distribution?
To address the questions about the injectors for 52Carl and distribution concerns for panic:
The injectors are batch fired and can be tuned out (turned off in configuration settings). Running a dual system (two throttle bodies), driven 1:1 just like a set of carbs, each throttle body will have a driven injector to distribute fuel as normal and a second driven or second batch. Since the system has two injector drivers, the second injector is driven and only comes into play when demand requires it. If I used the injectors from my base system (which are 100lb or 1050cc), they would be able to support up to 650hp. So I have elected to use a smaller 37.5lb injector (394cc) for the system, which are enough to support about 240hp (using all four driven at 80%). Essentially, all four can fire at a low duty cycle and increase output as load requires, especially if even small injectors are used.
Cylinder to cylinder distribution on these engines are always a concern and depending on the intake design, things will vary. If this was setup as a single unit (1 barrel), naturally cylinders 3 & 4 get more fuel. The advent of the 2x1 intakes helped alleviate some of this, but added complexity in tuning. Then with the 3x1 intakes, you got better distribution, but we all know this. I have actually plans to test and tune a 3x1 system and the components ready to go.
The invention of fuel injection (from the original mechanical) helped add hp, but has its complications. As things progressed, TBI, TPI/PFI, then GDI have made massive advancements in fuel control capabilities. So, I am merely using what newer technology I can to create a simple system that will provide some advantages over the old carbs on the 261 engine that I building. The better fuel atomization in itself will lend a hand when it comes to distribution issues. The closer you can get gas to being gas vapor, the less likely it will have flooding and fouling issues. The ECM will monitor that via the wideband (adding a secondary wideband monitor (or thermocouples) on each manifold prior to the merge, will help in tuning, but this is overkill as the motor itself will not require this amount of accuracy).
Now, just a little background on myself. I have done work in several fields over the years as an engineer and have been in the automotive field for more than 30+ years. My last job I helped develop a fuel management components and active cylinder displacement/deactivation components.
