EFI Considerations?

[mtm6486]

I am just curious what all is required for an EFI conversion. I have a '69 with the original 302. It is currently running with a carb, but I am curious about the EFI swap. I don't have a wiring harness yet, so I want to make sure I buy a harness that will work for the carb and is capable of EFI if I decide to do the conversion.

Any recommendations for a reasonable wiring harness capable of carb and EFI?

What are the other considerations an EFI conversion? Ballpark of what the conversion will cost?

 

[Broncobowsher]

There are so many different ways of doing it. There really are no universal answers.

Any EFI will work with any body harness. There are only a couple of wires that actually mate, usually just one, the Ignition on signal.

The simple EFI would be a 2-barrel Sniper on your existing engine and manifold. The mustang based EFI was popular but is being replaced with EFI off an Explorer. So many options.

About the only thing they all have in common is the need for fuel system changes. High pressure fuel supply. An electric pump, some sort of regulator, return line. Again, too many options and many will be based on what EFI you go with.

 

[jmhend]

There are so many different ways of doing it. There really are no universal answers.

Any EFI will work with any body harness. There are only a couple of wires that actually mate, usually just one, the Ignition on signal.

The simple EFI would be a 2-barrel Sniper on your existing engine and manifold. The mustang based EFI was popular but is being replaced with EFI off an Explorer. So many options.

About the only thing they all have in common is the need for fuel system changes. High pressure fuel supply. An electric pump, some sort of regulator, return line. Again, too many options and many will be based on what EFI you go with.

X2, there are so many options. With options come opinions.... it would help with a little back ground on the why....

mtm, most of us want EFI for one reason or another. Cold starts, off camber fuel slop, etc... what are you hoping to achieve (or resolve) by going with an EFI setup?

solutions in my opinion are generally going to cost around $1,000.00 it can be done for less or a LOT more depending on what you can do yourself or how far you want to go.


I sourced a 90's mustang 5.0 (computer, complete engine and trans for $500) then had to get (well it just made things easier) a RJM harness (https://www.ronfrancis.com/prodinfo.asp?number=TDZ-75) for roughly $600. Plus a high pressure fuel pump and return line to the tank.

Hope it helps. feel free to pm me if you have specific questions about my setup.

 

[rguest3]

As stated, the EFI systems use a Stand-Alone harness and ties into the existing Bronco wire system with a couple wires. Some just a Battery + and a Switched Power.

Look at Painless, American Autowire and Centech for the Chassis harness. (To replace ALL the wiring on your Bronco) All of these kits have extra circuits to power the EFI you will be adding. If you are keeping the rest of your Bronco completely stock, then I would recommend the Painless, Bronco specific Harness. Most of the wires are terminated and it's almost a Plug and Play install with Ford Factory colored wires too.

For your Stock 302 engine, I would go with the 2-Barrel Holley Sniper (Original 2B Intake) or the FiTech 400 base version (4B Intake).

Most of your time for the conversion will be setting up the Fuel System. These are also available in Kit Form as well.

 

[Allen_69]

Sounds like you are having the same conversation I've been having. Here's some of my thought process

My current engine is a 1980 302, nothing special, however It has always run fine without issue.

I could piece together all the parts for an explorer or a mustang FI conversion, and order a harness to make the install easy, and add the fuel components. Based on my spreadsheet calcs this came to about ~$1000, and an afternoon at the junkyard

I could order a Holley Sniper system for ~1300.

I'm now at an age where I like the idea of putting New parts on my bronco rather than worrying if the part I grabbed from the Junk yard was bad.

If I was in my 20's the idea of spending 300 more would have been out of the question.

 

[76YETI]

I've also thought about the conversion, until I read the countless threads involving all the problems that arise. I recently read an article where one of the builders quit using the throttle bottle fuel injection (I think Sniper) because of reliability. https://www.edelblog.com/tech-tips/...i-with-the-edelbrock-pro-flo-4-multi-port-efi
My motor starts right up and I would hate to start chasing gremlins...some day, maybe!

 

[BGBronco]

I did FiTech. I read all the issues, procrastinated for 6 months and finally did it a few months ago. I have been very happy with it and not had any of the issues people have described in many of the threads. I upgraded to the 23 G tank with an internal fuel pump at the same time. I have the painless harness but haven't installed it yet. From what I've read, any harness will work, even my factory original one!

 

[sanndmann3]

I recommend the EDIS system that is found on 96-01 Explorer 5.0 engines. I'm guessing it is going to be much more reliable than aftermarket stuff. Get with EFIGUY here on the forums for computer programming and harness rework.

 

[73azbronco]

Tip, buy everything you need at one time. Prevents you from what I did which is buy one thing here or there and end up going another way after years...

 

[Broncobowsher]

Beware of hidden issues. For example, the Explorer EFI as mentioned above. Everything will bolt right to the engine. Firing order is different but with wasted spark it will still run. But you may have some driving issues with injectors not firing on the actual intake stroke. Happen several times before with mustang EFI on old engines. Another is the cam sync / oil pump drive will be for a roller cam and the old engine will be flat tappet. The cam gear will mesh just fine and probably last a few thousand miles before the gears self destruct and send metal filings through the engine.

There really are issues with just doing a quick modern EFI on an old engine. Often the whole engine will just be swapped with the EFI in place.

As for the dishing of the Sniper, keep in mind that the site is Edelbrock and they are trying to sell there own stuff. Of course the competition will be junk that just will never work right and there own stuff will be perfect. When you can't get independent advertising to say Holley sucks, you make your own. There are a lot of happy Holley Sniper owners out there. Yes, some will have issues. But you really don't hear that many.

 

[Timmy390]

No sliver bullet for sure and no doing things half way.

All EFI systems will require a good charging system. Low voltage will cause all kinds of odd issues and have you chasing your tail. Need good grounds too. All the EFI systems will work with the stock harness. Only 2 or so connections are needed and those are at the ignition switch.

EFI likes higher engine temps so factor that in.

I did mine all myself with the exception of the ECM programming which EFIGuy did. I've had zero issues in 2 plus years. Well none related to the EFI conversion.

IMO, if sticking with a 302, the Explorer swap is the best. All of it, enginn front dress and EFI. Upgraded everything.....That said I'm considering a TB EFI for my 69 Stang

Tim

 

[onpier55]

I recommend the explorer swap. Pull one from a running explorer. Sell of the leftovers. Just finished my build. Ran great down to the wild horses roundup.

 

[mtm6486]

Thanks for all of the advice. My only reason for considering EFI was to make it a little more reliable for daily driving. I think I'm gonna stick with carb, I don't want to be chasing any electronic gremlins.

 

[67mustang390]

I am just curious what all is required for an EFI conversion. I have a '69 with the original 302. It is currently running with a carb, but I am curious about the EFI swap. I don't have a wiring harness yet, so I want to make sure I buy a harness that will work for the carb and is capable of EFI if I decide to do the conversion.

Any recommendations for a reasonable wiring harness capable of carb and EFI?

What are the other considerations an EFI conversion? Ballpark of what the conversion will cost?

ive had this same question. Thanks

 

[DirtDonk]

Any recommendations for a reasonable wiring harness capable of carb and EFI?

As I think you probably grabbed from what was said, there is no such need.
If your carburetor runs now, you don't need a harness. If you swap in an EFI setup, you use whatever harness you need for that particular EFI alone. The chassis harness remains the same.

If you were talking about a complete vehicle re-wire first though, separate from the EFI and then EFI later, then that's another conversation for what harness suits your needs and wants and budget the best.
Because none of them are going to be carb or EFI-centric.

Basically to run EFI you need 12v constant, 12v switched and ground connections, and maybe a tach signal. That's it. Most any harness, even the original in certain conditions, will work.
The rest of the EFI wiring is specific to the particular EFI.

If you're going to stay carbureted for now then, you can fire away at questions about just the wiring harnesses if you still want to re-wire.

Paul

 

[SteveL]

I've been slowly gathering parts to go explorer efi on the next 351w but the more I'm reading the more I'm thinking my carb has never let me down. Well there was one time I filled it with mud but it still was able to keep wheeling all day and made it back home. Going back to a stock hood will solve that problem.