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The Great EFI Debate

Discussion in 'Engine and Drivetrain/Mechanical' started by JonnybravoM3, Jan 29, 2018.

  1. JonnybravoM3

    JonnybravoM3 Member

    As I'm busy ordering replacement parts online for my classic, i constantly find my finger hovering over the Holley EFI kit... don't know why I'm itching.

    I love the idea of an easy reliable turnkey system, but I'm new to this carb game and have yet to really experience it.

    Am i missing out? If i board the EFI train will this kill the classic car experience?

    What are the experiences of members who have done this and for those who have not, why haven't you?

    Im in no rush, so far the car has not given me any issues and she's a once or twice a week kinda gal (not a DD). So rather than adding the kit to my shopping cart, it's been added to the wish list.

    Happy Monday!


    Sent from my HTC U11 using Tapatalk

    Sent from my HTC U11 using Tapatalk
  2. Horseplay

    Horseplay I Don't Care. Do you?

    Switching to an EFI system (especially if you go with a basic carb looking piece) really doesn't do anything to take away from the classic experience except do away with all the normal potential carb issues like hard starting, mixed throttle response, etc. To almost all but the very discerning viewer most people would never know you made the switch. For the owner/driver the car will become much more enjoyable as the reliability, performance and even fuel mileage all improve quite a bit.

    That said, it is not a simple bolt on as many novices can be led to believe. It involves a fair amount of work and knowledge to make the change as well as $$$. Even on the cheap side you're likely looking at a couple grand to make the switch. Aside from the unit itself you'll likely need a new fuel tank, pump, filter assembly and fuel lines. Most set-ups require both a feed and return line. The best systems also have the ignition system also controlled with the EFI to handle complete engine management.

    The good news is today's systems are not all that difficult to install for the above average home mechanic. It just takes some time and the right tools.
    Grabber70Mach likes this.
  3. 3175375

    3175375 Well-Known Member

    Prioritize your wish list n get educated in these systems. Holly, Edelbrock, Megasquirt and others all make them, depending on $ and how deep you want to get into the engineering and analysis of them.
  4. tarafied1

    tarafied1 Well-Known Member

    I like Carbs. You can tell by looking at my gut... oh wait, different carbs. But I like those too. However, I am old and grew up with them. Rebuilt many since my early teens so they don't scare me. With that said I am not opposed to EFI. My son has a 1980 Mercury Bobcat that we are going to switch to EFI. Mostly because he wants to add a turbo and we think it will be easier to do with EFI. It will be my/our first attempt to upgrade an older car to EFI. But again a properly tuned and maintained carb will start and run fine. We have a few that we daily drive and they don't like super cold weather but they still start and run. They are a bit fussy in sub freezing temps but everything else is okay. I like being able to fix it with a screwdriver and carb cleaner. Can't do that with EFI... My other son did a DOHC swap and has EFI. When it gets fussy it takes a lot of diagnosis and some times $$$ to fix. But neither of the EFI projects we have will be or are aftermarket bolt-on stuff so that is a whole different world. My 502 BBF will be an 850 carb but I have been considering the Holley Stealth EFI in the future. Time will tell.
    0ur12 likes this.
  5. JonnybravoM3

    JonnybravoM3 Member

    Right, so I've gone and ordered this because it's bound to happen eventually and i want some predictability with my classic when if i travel for 2 weeks and come back i don't want headaches starting plus i live in a warm climate so would like to use the car over summer as well in 115 degrees!


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  6. Horseplay

    Horseplay I Don't Care. Do you?

    That's a pretty sweet deal. I paid that for just the same EFI unit. You'll still need a return line set-up and likely want a new tank but that's a good way down the path. Personally, I went with an in-tank pump for a variety of reasons but in-line units can do just fine. You should also install a good tank vent that works well in a high pressure EFI system. Another reason why a new tank with welded in bungs for fuel and return lines along with a vent is a logical choice. I elected to use a Tanks Inc unit and a Walbro pump. VERY HAPPY with the way it all came together and functions.
  7. Boom

    Boom Active Member

    That is a nice deal. I have a Fitech unit on my coupe, been used as a daily for the last 3 years and no issues.
  8. 3175375

    3175375 Well-Known Member

    go get 'em
  9. JonnybravoM3

    JonnybravoM3 Member

    Great thanks. The support at Summit Racing recommended this unit and they said it has everything in it including the return line etc.... They said i would not need a new tank when i asked.

    Let's see how this goes. So you say it's a good system? I read mixed reviews but I'm still gonna try it out.


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  10. JonnybravoM3

    JonnybravoM3 Member

    I'm curious if anyone has gone EFI and regretted it?

    I'm not a purist, but i also feel guilty that I'm killing the classic touch?

    Sent from my HTC U11 using Tapatalk
  11. Horseplay

    Horseplay I Don't Care. Do you?

    The customer service at Summit is really good. The actual tech knowledge as it pertains to specific applications...not so much. Hit or miss. Your current tank does not have a provision for a return line connection. It looks as if the kit comes with a fitting that would clamp into a hole that would get drilled into the tank. Personally, not a fan of drilling that hole in an old tank. Give me a leak proof, solid welded bung. If you do go this route, make sure that the tank is thoroughly cleaned out when it is out of the car. You don't want any old rusty scale and such contaminating the new fuel system.

    I'm surprised you found mixed reviews on the FiTech system. Up until just recently with the release of the Holley system theirs was the go to for applications like yours. The only negatives I found were really just issues individuals had setting it up. More their problem than the actual FiTech. I think you will like it.
    JonnybravoM3 likes this.
  12. JonnybravoM3

    JonnybravoM3 Member

    Really is there no way around the tank drill? I asked about this and they said no. Could they be mistaken? If tank is drilled then arguably this process is not reversible in case a future owner wants to take her back.

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  13. Horseplay

    Horseplay I Don't Care. Do you?

    There is no stock provision for a return line. A hole has to be made to which a connection can be made to affix the return line.

    Don't worry about altering it. If the next owner wants to take it back to original they can simply buy a new tank. Along with all the other stuff you will have changed along the way. It's your car NOW. Do what you want with it...short of something stupid like adding a giant wing on the deck lid. A guy could (and should) get his ass kicked for stuff like that!
  14. JonnybravoM3

    JonnybravoM3 Member

    So i guess i better cancel my order of neons and spinners....

    Sent from my HTC U11 using Tapatalk
    tarafied1 likes this.
  15. stangg

    stangg Active Member

    You don't necessarily need a new tank. If your tank is fitted with a drain plug, you could just plumb the return line into that threaded hole. I believe it's an NPT, but I don't recall the size. Another option is to buy a sending unit with a return line already fitted in. When I did mine around '06, I drilled a something like an 1/8" hole into the sending unit plate, then dimpled the hole stretching it to tightly fit a 5/16 steel return line, then soldered it to seal it up. The only real drawback to using the stock tank is the lack of baffles so when running low on fuel, the pump might draw some air. Keep more than 1/4 tank of fuel and not a real issue.

    My son is building a 396 chevy. Contemplated between FiTech and Holley. read some about some issues with FiTech and the lack of support and ended up going with the Holley Sniper. Supposedly easier / faster bring up, better user interface. We'll see in the spring if it lives up to what folks say about it.
  16. kb3

    kb3 Well-Known Member

    I also added the return line to a new sending unit. It has worked flawlessly to this point.
  17. RapidRabbit

    RapidRabbit Well-Known Member

    Well im a little late to the party, but i changed to EFI in my stang as well.

    However I'm in the other category of systems. I dropped a complete engine and trans from an 88 mustang 5.0 in.

    If I could go back in time, I would have done a bolt on EFI instead. I would still do EFI though. I took my car on the hot rod power tour last summer and averaged in the 20s for mpg. The car ran great, always fired right up.

    For return lines I used a stock style fuel sender with a return line added in, but I think I'm going to change it to an in tank unit when the budget permits.

    Sent from my XT1058 using Tapatalk
    tarafied1 likes this.
  18. sportsroof69

    sportsroof69 STREET CAR

    You can add a sump to the stock tank and fit it with 2 bungs. That’s how mine is. Easy peasy.
    tarafied1 likes this.
  19. 0ur12

    0ur12 New Member

    Here's THE VALUE PLAY---- Hi Riser ( intake manifold ) and a HOLLY 670/770 Street Avenger will do everything you want for up to 427 cu.in. Costs around $600. The "come on price" for a F,I. is TWICE the carb set up!!! AND when you are all done and it runs Ok____ YOU WILL BE KISS'EN 3 GRAND. You just have to use your brain and books to learn about carbs.
  20. Horseplay

    Horseplay I Don't Care. Do you?

    What EFI set-up have you used that you ditched in favor of returning to a carb?

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