Anyone Do a Fuel Injection Conversion on a 351C?

[Silverback]

Just what the title says, has anyone converted to fuel injection on your 351c? What did you use? How did it work? Are you happy with it?

Not that it matters much but mine is a 71 M code (I'm pretty sure it's the right short block, I really need to check that _if_ there is a difference, but it has 2bbl heads on it and an aftermarket intake), I actually wish i knew the compression on this thing (the more I type the more I think I need to find all the casting numbers, even with that it would only be a guess on a 44y/o car...). I'm guessing between some of the accessories, the braided lines, edelbrock and FMS parts... and the way it _trys_ to idle it's been messed with..., either that or I suddenly forgot how to tune a carb :-/

 

[Jeff73Mach1]

I have not done it, but there are a number of folks that have. There are multiple ways to accomplish it from something as simple as a stand alone throttle body unit and an electric fuel pump, up to some more sophisticated units with injectors mounted near the end of the intake runners. The ford EEC computers are pretty versatile and a 351 Windsor based system would likely be a good candidate to make work, though the manifold won't work.

I think it would be a great upgrade for a lot of cars, but I like my carburetor

 

[71mach1lady]

We installed the Powerjection III from Professional Products and we happy with it so far. Still need to get enough time on it and then tweak it some

 

[Mister 4x4]

I have an Edelbrock E-Street FI system waiting to go on my 351C-2V as I type this. Unfortunately, making time to get it and the other things I still need to do to get the car on the road has been a major challenge for the past several months.

Pathetic... I know.

 

[jbojo]

I have the MSD Atomic EFI and no problems so far. Only 200 miles on it now.

 

[will e]

I ran a Holley projection unit for a while. It was the older analog version. It worked fine but nothing special. The older holley analog units are very simple with very few inputs. This is both a plus and a negative. Tuning was easy but not exact.

Personally I wouldn't bother with a TBI kit. It is only slightly better than a carb since both are 'wet manifolds'. And since our engines were not designed for fuel injection you will compromise some with a port fuel injection system. But between TBI or port I would go port. Much more tunable.

What are your reasons for considering fuel injection?

 

[Omie01]

Correct me if I'm wrong, but with F/I isn't the amount of fuel that gets delivered restricted by injectors? Limiting how much power gets made? I thought I read somewhere F/I can only get up to 900-1000 cfm?

 

[71mach1lady]

Isn't the fuel always limited by something? Injector size can be increased and pulse width changed. It sure is nice to reach in the window, turn the key and within a couple of revolutions she fires. No stepping on gas pedal twice before turning the key. No choke to stick, just a programmable IAC circuit. We need to get enough miles on our Mach to really get this dialed in but for our lightly built M code the EFI system can deliver all fuel we can use

 

[Don65Stang]

:worthlesswithoutpics:

 

[InjectedMach]

I have to make this point, an engine - any engine, does not know how the air and fuel is being delivered. I think sequential port is the best and now direct injection puts it IN the chamber directly so those engineers have upped the game again, more power more economy.

I have Used MassFlo EFI with no problems on 351C,427 and 410...and now working on a boss9 setup. Its the best system I have run accross so far. They are all light years ahead of carbs for tuning, drivability, troubleshooting...... my $.02. The fast system did not control timing and the cam profile was too radical with my 427 and 410 for it to generate data for idle A/F. Those engine made 10" and 10.5 vacuum respectively and they dont tell you outright but FAST, Powerjection and MSD will be super rich (foul plugs rich) if they can even idle. You dont have to believe me, just place a call to the support lines and ask directly and they will then admit to it.

as far as power limit, FAST and Massflo have 2 x 4 Venturi style throttle body configurations coupled with larger higher volume injectors, and you can run forced induction through them as well.

Massflo has triggers for up to 3 stages of nitrous, FI and the cubes dont matter

 

[jbojo]

Correct me if I'm wrong, but with F/I isn't the amount of fuel that gets delivered restricted by injectors? Limiting how much power gets made? I thought I read somewhere F/I can only get up to 900-1000 cfm?

The MSD unit is rated up to 975 cfm and up to 550hp with standard injectors. If you upgrade the injectors then 850 or so hp.

Agree with Mach1Lady, it's nice to just turn the ignition switch and it starts right up. Also you can get in it and drive off when its cold with no stumble or it dying. Another advantage is that it will adjust to high altitude changes without having to manually adjust the fuel/air mixture.

Lastly the units can automatically adjust the engine timing based on the motors requirements. The distributor no longer has any springs, weights or vacuum advance to mess with an it's basically a shaft and rotor. The EFI tells the ignition when to fire the cylinders and you never have to time the distributor again. If you want to increase engine timing, idle rpm, a/f ratio or a slew of other settings you just enter it into the handheld and you're done.

I am not saying that carbs are not any good but 43 yrs of technology does wonders to motor performance. Can't do this with a carb and the TBI units look like a carb.

These features are what is available with my setup and may not be available in all systems but I think most systems can do the above.

 

[Jeff73Mach1]

Injected Mach-I've followed a few of your posts and it looks like you know what you are talking about.

I do disagree with the statement "any engine, does not know how the air and fuel is being delivered" (Though technically an engine is a collection of inanimate parts and never "knows" anything)

Carburetors and Throttle body injection systems deliver their charge in a different matter than port injection, such that the atomization of the fuel causes a cooling effect on the air. This difference can be tuned around or can be perceived as a disadvantage to port injection if one is so inclined. I believe that the proliferation of cold air intakes is a direct consequence of this phenomena.

A well integrated Fuel injection setup is great for both driveability and performance. A well tuned carb and ignition system can make equal or even greater power in some settings. Cost is a big factor as well as comfort with understanding and tuning the system.

and a carb sucking air at 7500 rpms makes a very satisfying sound

 

[Mister 4x4]

I think you're confusing the terms "port" and "direct."

Port injection has the injectors mounted to the intake manifold ports just ahead of the intake valves, timed to fire slightly ahead of the valve opening - external mix of fuel & air sucked into the combustion chamber through the intake valve.

Direct injection has the injectors mounted to the cylinder heads, spraying fuel directly into the combustion chamber, timed to coordinate with the intake valve opening - internal mix of fuel & air right in the combustion chamber.

http://thechronicleherald.ca/wheelsnews/26226-direct-vs.-port-injection

Throttle body injection, Multiport injection, and carburetors all feed the system in the same manner - air & fuel are mixed external to the combustion chamber - all affording the same kind of 'cooling' effect you mention as well.

And No - the engine doesn't care how it gets its fuel & air mix: it burns whatever is in the combustion chamber at the time it's told to fire the spark plug... that's why we tune them for optimum burn, performance, and longevity.

Dear God, Omie - are you serious that 900-1000 cfm isn't enough?! What are you planning on running, anyway - low 7's in the quarter?

650-750 cfm on a warmed-up street performance engine should be plenty.

 

[Jeff73Mach1]

I'm not confused-Port injection cannot have the same cooling effect as throttle body injection-the time between injecting and reaching the chamber is much shorter (Yes, I know we are talking milliseconds, but the cooling effect requires some time. Here is a paper testing this theory in a slightly different scenario, but it is relevant

http://papers.sae.org/2012-01-1284/

 

[Mister 4x4]

Point taken, but I ain't gonna lie - I have no idea what I just read... The abstract talks mainly about the difference between port and direct injections, and the difference in knock ranges between gasoline and E85 - no mention of throttle body or carbs.

The whole point is academic, IMHO, for the purposes of the average guy who wants to substitute a carb for a more efficient and simpler to operate fuel delivery solution. Getting into the weeds of efficiency tuning is interesting at best... but I think most of us just want the ability to hop-in, turn the key, and start driving without having to wait for some magical point in time where everything is in the zone of operational happiness.

 

[jbojo]

:worthlesswithoutpics:

Pics you want, pics you shall have

This is the MSD setup

I have it setup so that it controls the engine timing and the two cooling fans. All of the red items are the MSD parts that I used to get this all working together. The pic of the distributor shows all the guts removed and the advance plate is locked so centrifugal advance plate can no longer move.

This system can use a return or return-less fuel system and I chose to use a return one. Using the return line reduces vapor lock issues that can occur on hot days. I used the fuel evaporator line to be the return for the gas since that line was already there and connected to the fuel tank.

Only drawback was the amount of wiring that has to be done and hiding it all.

EDIT: Attached the manual that may help.













atomic EFI Manual.pdf

 

[will e]

So if one carb is as good as a TBI then three carbs must be better?





Well, not really. It's kind of temperamental. And I am still dialing it in again. Performance wise a good 4bbl is better than my three carbs but I am happy with the setup.

If I didn't have the tripower I would probably consider either webers or maybe something that would support a Paxton style super charger.

 

[71mach1lady]

Here are a couple of pictures of our set up

We put the 6AL unit under the dash, out of sight

The ecu in onboard on the Powerjection III so it is a nice compact package. Timing control is handled by the unit so we picked up an MSD distributor and locked out the advance. Unlike the MSD or Holley units there is no provision for fan control with the Professional Products unit

We painted the MSD coil black and ordered their black distributor cap so it would all blend in

 

[Jeff73Mach1]

The whole point is academic, IMHO, for the purposes of the average guy who wants to substitute a carb for a more efficient and simpler to operate fuel delivery solution. Getting into the weeds of efficiency tuning is interesting at best... but I think most of us just want the ability to hop-in, turn the key, and start driving without having to wait for some magical point in time where everything is in the zone of operational happiness.

I don't disagree with you on this matter. I was simply pointing out that there are factors that differ between the various systems.

There is no magic to a good tune on an ignition system or a carb-fuel injection may be easier for you, but not for me.