What is all needed to convert to EFI?

[Najib]

So im looking to throw dual efi carbs on my 73 charger, I am going with Holley sniper dual efi carbs for my 440 tunnel ram with a 727 auto behind it, I know I have to get a fuel pump and gas tank, but apart from that what else, fuel regulators etc?

 

[tonysrt]

A fuel gauge to see how much pressure you have because most F.I. use about 58 psi. You may have to run a return line to the tank and a lot of fittings for the higher pressure you'll have. It's not a cheap installation. I have an Edelbrock pro flo 4 on a gen 2 hemi and there was a lot of after market parts I had to buy beside the F.I. from edelbrock.

 

[BeepBeepRR]

So im looking to throw dual efi carbs on my 73 charger, I am going with Holley sniper dual efi carbs for my 440 tunnel ram with a 727 auto behind it, I know I have to get a fuel pump and gas tank, but apart from that what else, fuel regulators etc?

Pretty sure the Holley Sniper EFI is internally regulated. If you get one of the master install kits it will come with just about everything you need to install. However the filters and pump will be external from the tank. Unless you buy one of the Sniper fuel senders/pumps that fit directly into the OE tank. They make it so you do not have to use a return line. I was looking seems they don't have the in tank sender for your car yet.

 

[yella71]

Everything you dont have related to EFI. So If you have nothing you need everything

 

[Wietse]

Sniper EFI has internal regulator, so it will need a return line.
I went for an in-tank fuel pump with integrated pressure regulator at 60 psi, so only needed to run a supply line to the engine and blank off the return outlet on my sniper stealth.

Jus see first what is available for your car model on fuel pumps, preferably a kit with integrated pressure regulator.
Once you got that planned, the rest is easy.
Run the correct size fuel line, specially for 2 units.

 

[hanks73340]

Don't forget the O2 sensor to the exhaust. You should be getting the hand held device that will show all of the pressure settings, temps and flows. If buying the whole kit, instructions are pretty clear on what you will need. I ended up with the Fitech Street series EFI and love it. Good luck.

 

[diesel_lv]

I used a Fitech which, except for the tunability, is about the same as Holley Sniper. Ran an external regulator back by the fuel tank w the throttle body regulator blocked off n no return, had issues w surging fuel pressure due to the distance. Was told by Aeromotive to either have regulator near throttle body, which would require a long return line or use the throttle body built in one which also requires the long return line. I'm using AN adapters on factory 3/8 line. Then ptfe 3/8 braided w adapters from factory line to throttle body. Same for return. I was able to run 2 factory 3/8 fuel line side by side.

 

[70chall440]

So much has been written about this subject and there is so much information online. You are going to need

• The EFI system of choice (in your case the Sniper)
• EFI rated fuel filters (2 of them, a 10 and 100 micron)
• EFI rated line (Rubber, SS braided, steel)
• The various fittings to connect the line
• EFI pump (in tank is highly recommended)
• A quality regulator
• A good electrical system (100A or better Alternator depending on what else you are running in the car, improved wiring, good connections)
• O2 bung in the exhaust system (your EFI kit probably comes with the sensor and the bung)
• Fuel pressure gauge (usually mounted on the regulator)
• Wideband O2 gauge (optional)

 

[Dennis H]

Real EFI is the DPI like the Pro Flo 4. Sniper is TBI, essentially an electric carburetor.
Otherwise $$$ for the fuel delivery system not to be underestimated.

 

[70chall440]

The fuel and the electrical systems are usually the things that most don't think about until its biting them in the backside.

The fuel system is generally pretty straightforward in that you need a pump, filters, fuel line and fittings, however it can get overwhelming pretty quickly. The easiest/cleanest way to do it IMO is get a Tanks Inc. tank (assuming they make one for your car), one of their in-tank pumps (sized to match the engine demand), 2 sets of replacement fuel lines (3/8 feed 5/16 or 3/8 return), then some soft line (rubber, SS braided, nylon braided, etc.) with the fittings to make it work. You can get hard line adapters to adapt the hard line to the soft line which is pretty simple. Then its laying it all out, mounting the 100 micron filter somewhere that you can get to it, mounting the regulator someplace, then installing the line and connecting everything. You also need to use a relay for the fuel pump which will most likely be connected to your EFI ECU.

The electrical system is where most of these conversions fail or cause huge problems to the point that many rip the EFI off and go back to a carb. EFI MUST have good clean steady power and if trying to adapt it to an old wiring harness with a stock style alternator is a sure way to create problems. The electrical system needs to be updated so that the alternator is connected to the battery directly (not through the ammeter), the EFI needs to be connected directly to the battery (both positive and negative sides). The alternator must have enough capacity to power everything and still yield enough steady power for the EFI. This takes some ciphering or calculating to determine what the power (amps and volts) are for the vehicle to allow selecting a compatible alternator.

 

[TN Mopar]

We did the fuel system conversion this weekend
I am running a Billet 850 so I highly doubt I will go EFI
However I was tired of the noise my electric fuel pump made as well as going through fuel senders trying to find one that works
I also wanted a return line to keep fuel fresh and cool
We used the Tanks inc EFI tank, GPA4 pump, floatless fuel sender, steel braided lines (8an feed 6an return) return, a return line regulator (for Carb 4-9 PSI), Plumbing fittings and clamps to hold the lines
All total about $900

The install was straight forward although running the vent lines took some thought keeping all of the lines away from heat
it took 40 feet of line (20 of each) with only a little left over

The Tank filled very fast while pouring the gas back in so the vent lines work
The sender seems to be very responsive. It reads a touch off but I had a meter match installed and haven't adjusted it yet
However in driving the car the gauge needle dropped as it should and I am hopeful the meter match wont even be needed
I will do more testing as weather allowed

The pump is very quiet. you can hear it if the car is not running but like any modern car it is just a quiet hum unlike the electric pump that I had on it

Over all I am very happy

 

[Don Frelier]

The electrical system needs to be updated so that the alternator is connected to the battery directly (not through the ammeter), the EFI needs to be connected directly to the battery (both positive and negative sides)

I converted mine to MSD atomic in 2015.
The atomic is connected directly to the battery. Atomic has the ability to do pulse width modulation on the fuel pump which helps a bit with noise and power draw.
I have electric fans as well (3) and my alternator goes through the ammeter.
I haven't had any issues electrically since the install.
When both fans come on after a stop on a warm/hot day it does go towards the second mark on the ammeter but not for very long.
After 5 minutes its dropped down towards the first mark and by 10 minutes its below the first mark.
I may bypass the bulkhead in the near future but I just put a new engine harness in it and the bulkhead connection was in good condition.
I really like having an ammeter in the system I can see what's going on with the charging system clearly.

 

[Derwud]

3 installs of Edelbrock Pro-Flo 4.. Everything @70chall440 says.. I run 10 Gauge wires back to the Battery just for the EFI.. Clean Power and Fuel are KEY. Also don't forget throttle cable and kickdown..

 

[Derwud]

By the way, it's all @Dennis H fault!

 

[6872n73]

Also make sure your grounds are in very good shape. Battery to body, block, heads, and anywhere in between. Good clean preferably with my own corrosive grease on all the joints.

 

[Wietse]

Another tip is to use a relay for the fuel pump power supply and let the relay be switched by constant ignition 12V.
I even put a manual switch on the ignition wire hidden behind the dash....my anti theft system.
Get the +12V direct from battery with fuse, relay and as mentioned 10 gauge wire to ensure that pump gets the juice it requires.
And to be really safe, get one of those power cut out switches that turn off power on impact/accident. (some sort of G-force activated things, don't know the name lol)

 

[matthon]

Ground and power hubs, redid wiring, Tanksinc, not their in tank pump, PTSE lines, iirc Fragola fittings easy, Denso alternator, made my own linkage for a few bucks, etc.
And this filter/regulator next to the tank, no car length return, easy access to filter.
https://www.summitracing.com/parts/wix-33737

 

[69ChargerR/TSE]

Did you figure it out? If not let me know, I have the Holley Sniper Stealth EFI set up, and can help.

 

[threewood]

Update - We moved to NM where the elevation is about 3900 compared to 70 feet above sea level. Car runs great without any tuning.

One weird issue that occurred was a surging at idle after driving around. Happened twice. Most recently was yesterday as I was driving around pretty fast. Noticed that the IAC would bounce from 0 to 50% . I checked both vacuum lines for leaks, pulled the IAC connector and ran without it. No surging. Plugged it back in and the surging came back. Went into the menu and found IAC settings. Found that an A/C IAC step up setting was on at 50%. Turned it to 0%. Problem solved. Not sure how it just turned on and became an issue.

 

[moparnascar]

looks like I came to the right place! I am building a gen 2 472 Hemi. Edelbrock Pro Flo dual throttle bodies port fuel injection. Going to use for street and fun. Do any of you f=guys have a cam recomendation? I want to pop hood and look mostly stock. My shaker will cover most of the EFI. I want to start easy with key and be a bad *** if I want it to.