Gathering thoughts and info for possible EFI project.

[66FAIRLANE]

Just doing a bit of deep thinking about a project I have in mind. Will be freshening things up soon (well probably next year) and will most likely go 445 but thinking about going EFI. I have always wanted to make my own throttle body so here is the plan.

Tunnel wedge intake with injector bungs and homemade twin 4 barrel throttle bodies. I think this would look cool under a standard oval air cleaner in my Fairlane. I am thinking to buy Holley throttle plates as I am assuming at this stage they would be elliptical and hard to make and go from there. Probably 600 cfm as there would be no venturi or boosters in the flow so they would most likely flow around 650+ each.

Don't know a lot about EFI but am thinking I would need the following.

Injectors
Fuel rail (could be custom as TW intake runners look to be uneven)
TPS
MAP Sensor
Throttle Bodies
O2 Sensor(s)
Pump and Regulator
Brain Box
Idle Air Control Motor

Have I missed anything? If I decide to go ahead it won't be for a while and after I have gathered any info/help needed in the tech section here I will start a project thread.

Any thoughts?

[GJCAT427]

Could you possibly use a pair pf 1850s gutted with the correct throttle arms installed? They are just going to flow air anyway. It would be a real deciever to the eye. I`m just thinking out of the box here.

[fe66comet]

I was going to take the same approach except use two GM 500 CFM throttle bodys and twin wide band oxygen sensors. The throttle body just needs the injector pod removed and a block off plate installed. Your CFM options are 450, 500 and 570, aftermarket throttle bodys come much larger. The other factor is you can buy adapter plates in rear, center and front to position them, also in any thickness and plenum configuration. I would go with the Holley HP system due to it's ability to configure to run two throttle bodys and two wide band sensors, also it is a self learning system with data logging. I have used this setup before and installed it for others, it offers excellent throttle response and way better fuel economy. Also it pulls consistent throughout the RPM range with no flat spots.

[jayb]

My advise would be to pick the brain box first, because that selection will drive a lot of your other selections.  If you are computer savvy, I'd suggest a Megasquirt system, because they are fairly inexpensive and well sorted out.  I've also used the FAST system with good results, although it was pretty expensive.  My ems-pro system worked, but gave me starting problems in some cases.  Both of my Mustangs are now running the Megasquirt MS3X system, and the Galaxie uses the FAST system. 

You will typically need an electronic ignition setup to use with the EFI box, either a crank trigger setup or a distributor with a "crank" sensor, and maybe a cam sensor if you want to go full sequential injection with the EFI.  You will also need an Air Temperature Sensor (ATS), Coolant Temperature Sensor (CTS), Throttle Position Sensor (TPS), and a Manifold Absolute Pressure sensor (MAP).  And of course the wideband O2 sensors for tuning.  Your fuel pump needs to be able to deliver the fuel at 45 psi or higher.  The idle air control motor is optional, and I have never used one; I just use a normal hard throttle stop.

I think rather than just buying the throttle butterflies you might be better off buying a carb base plate, and machining a top to fit.  Then you don't have to worry about the fit of the butterflies to your throttle body.

Last comment is once you go EFI, you'll never go back.  The tunability is unbelievable.

[fe66comet]

I did.not think the fast had programmable auxiliary inputs and outputs so you would.need.to run.two ecm boxes in series. Plus it is.not self tuning so you gotta monkey with it, I can do that but it is a real pain and.does not compensate for density or elevation.

[lovehamr]

I'm in the process of changing my carbed 462 over to Powerjection 3.  I chose it because I wanted the benifits of injection and looks of a carb (no big fuel rails on my vintage intake).  I'm still working on the plumbing, so no report yet.  But it does look promising.

 

This was over on the FFR forum.

[jayb]

Actually the FAST XFI box does compensate for density and elevation, via the MAP sensor and the ATS sensor.  It will also self tune to a degree, via the O2 sensor.  But for optimum performance you have to tune it yourself.

As far as Auxiliary inputs and outputs, if you mean functions like switching on and off cooling fans, electric water pumps, nitrous systems, etc., the FAST XFI box has all that too.  It also has extensive datalogging capabilities.  It is a very complete system, just expensive.

[fe66comet]

It will run two TPS sensors, Idle air motors and two wide band sensors also? I tried a tuner AEM system once, it was a constant headaches. It would run great one day, the next I had to change the fuel map. Not very dependable.

[jayb]

It will run two wideband sensors, but not two TPS sensors and two idle air control motors.  Why would you want to run two of those anyway?  Seems to me that a single TPS and single IAC motor is the way to go, if you even want to run an IAC motor...

[Heo]

Im about to build a 8 idividual runner efi with a jays intake
adapter and 8 Opel Omega (Vauxhal something in australia
i think)throtle bodys I have the intake figured out and on
drawings but the electronics i leave to the younger generation
After two strokes i have hard to learn new things
Kinsler have o good guide to fuelinjection some one
here gave me a The link in some of my threads

[fe66comet]

I thought he mentioned two throttle body's on a duel quad intake was what he wanted?

[jayb]

You don't need the TPS on both throttle bodies, just on the one that is the primary throttle body.  Same for the IAC.

[fe66comet]

How does the system know the position of the secondary then?

[jayb]

It doesn't need to know. The MAP sensor will tell the system how much manifold vacuum is there, and the fuel map adds fuel based on manifold vacuum.  It is a speed density EFI system, so the TPS sensor doesn't affect the A/F ratio.

[fe66comet]

Hmm good to know, my Jeep is my next injection project. I thought the lack of another IAC would starve at idle and make it stumble. I haven't decided on the manifold yet but I will need long runners and idle to 5500 power with lots of torque maybe tpi with raised runner Brodix heads. Yes it is a Gm GASP, CHOKE did I say that here. But will be a 383 stroker with monster 9 ford high pinion axles.