[JLMounce]

Some more information about the complete combination would be helpful. It kind of sounds like you're still flying a bit blind here if you don't yet have a compression ratio that the engine is going to wind up at, or that you're specifically shooting for.

Although I don't necessarily think it's impossible, getting 800hp from a 428 that utilizes worked factory heads is going to require more than 12:1 compression and it's going to likely need so much cam that you can pretty much forget about using any of the Sniper/Fitech type fuel injection units. While there are a handful of people that have gotten these things to run on engines with as low as a couple inches of vacuum, it's pretty well documented that if you're engine produces less than 5-6" of vacuum, you're going to spend more time fighting with the units and you're better off at that point with something like a Holley Dominator.

Now a 428 with a 260-280cfm stock type head, 12:1 compression and a cam in the 240ish range @ 50. That'd probably be in the high 500 to low 600 hp range and well within the grasp of what a Sniper could handle on pump gas or e85. You'd need the 8 injector model here to support that power on e85 and I'd run the Walbrow 450lph pump, F90000267. It's pretty basic setup from there. If the car will be stored without fuel and will be driven pretty regularly in the driving season, I wouldn't be worried about going with a Tanks Inc tank, a good quality PTFE push lock style hose and an e-85 compatible filter and the Sniper unit.

The initial tune up with the Sniper/Fitech deal is trial and error with e85. They don't specifically have tuning changes that can be made for e85, you kind of have to fool them a bit. The most common way people are doing this is to add between 20-30% to their engine size to adjust for fueling requirements. This method effects all fueling globally and is going to add that same percentage of fuel for all the breakpoints you provide. You provide those afr requirement in standard gasoline scale. Your display will read out standard gasoline scale as well, but the system is actually using lambda, so it doesn't really care what fuel is being used. It's just looking for stoich where lamda =1.

You can of course go the route of providing accurate information to the ecu as far as engine size is concerned, then command different afr values based on e85 scale at the various breakpoints. This is generally not as favorable however because of the interpolation going on and the fact that the gas scale and e85 scale aren't a 1:1 ratio from each other. Most people do not opt to tune the systems like this as a result.