I think the replica manufacturer is probably less important than the engine size and the fuel selection, in this case E-85. Additionally, E-85 may not be the best fuel for carbureted applications; more on that later.
If I recall correctly, that Carter pump is about a 190 lph pump that runs around seven psi, so you shouldn't require a fuel pressure regulator. My guess, and all it is at this point is a guess, is that if you have an 850 or so for your carburetor, the 190 lph P4070 will fall short of the mark.
A 427 cubic inch displacement engine at 6500 rpm, and let's go for a moderate Ve, say 95%, would put the engine's air appetite at ~53.6 lbs of air per minute at 6500 rpm. The next few metrics determine fuel consumption and establish a realistic power output along with the air and fuel consumed.
Let's use an E-85 AFR between 7 and 8.5 for maximum power. The 8.5 max power AFR would be a lean max power and likely to hurt parts over time. A 7.0 AFR would be a rich max power AFR that is safe on parts.
At an AFR of 7, you would require 7 lbs of air per pound of fuel. This means you would need 53.6/7 or 7.66 lbs of fuel per minute. A fuel appetite of 7.66 lbs of fuel per minute is 459 pounds of fuel per hour.
At 85˚F, E-85 has a specific gravity of 0.7784, which means it weighs 6.48 lbs/gallon. That means 459 pounds of fuel is 459/6.48 or 71 gph or 268 lph. A P4070 fuel pump is only capable of providing 190 lph.
The bad news gets worse. When accelerating, the AFR will need to be richened to somewhere in the middle to high sixes—let's say 6.75:1, probably more. The carburetor power valves and the accelerator pump (although primarily power valves) will be called upon to provide the extra fuel. At a 6.75:1 AFR, that means 476 lbs/hr, 73 gph, or 276 lph.
The engine is simply not safe with a 190lph pump. For a comfortable margin of safety, you should be using a fuel pump capable of 350 lph or more. While you could use two 190 lph pumps, you would be better off with a single ethanol-safe 430 lph TI Automotive F90000274 in tank fuel pump to feed the engine.
You should give serious consideration to using an EFI pump designed to deliver these higher fuel volumes. You would also use an EFI-style fuel pressure regulator in the engine compartment to regulate the fuel pressure down to 7 psi at the carb.
EFI pumps are much more robust, practically last forever, and are much more easily sourced than older 60s-style carburetor fuel pumps; plus, you can easily get away with a single pump.
After all that, you will still need an alcohol carburetor. Sadly, your problems do not end there. Pump grade E-85 can vary from E-54 to E-85 and still be sold as E-85! That means substantial tuning differences immediately after you fill the tank, depending on what you pump in there.
EFI cars handle this with ECUs, fuel sensors, and flex-fuel technology. There is no such thing for carbutretors. There is only another stop at your local tuner’s to get your retune until the next tank of fuel. E-85 seems like a good idea, initially, but falls seriously short of the mark for carburetors. If you have your heart set on E-85, go EFI. If you like your carbs, you should skip E-85.
By the way, here's some feel-good stuff: It takes approximately 10 lbs of air per minute to produce 100 HP on gasoline. If your engine consumes 53.9 lbs of air per minute at 6500 rpm, it will look like ~535/540 horsepower. If we give ethanol only a 5% step up in power over gasoline, pull out 50 HP for frictional and pumping losses, that will put your engine somewhere around the 510 HP mark or better!
Because ethanol is more resistant to detonation, you can safely run a more aggressive timing curve and compression. This will increase low-end torque and register very positively on your seat-of-the-pants dyno. However, it is impossible to precisely shape your advance curve with the distributor you currently have.
Although you didn't ask, I'll suggest that whichever route you choose, you should deep-six your current distributor and use a
Progression Ignition Distributor <= clickable.
This distributor allows you to tailor an advance curve like an EFI system using your smartphone—that's right, your phone! Equally as good, it provides an anti-theft capability that will absolutely shut down the ignition, making it impossible to start the car. The videos on their site have a bunch of other pretty cool stuff. Take the time to explore. You will not be sorry.
Fuel pump for E85 CA gas in a '66 427 FE
Linear Mode
