Ride along with me on converting to EFI

Instead of making a new thread every time I thought I would just make this one just in case anyone is looking to take the plunge.

I bit the bullet and purchased the Tanks Inc kit because I was tired of killing batteries waiting to suck fuel from the fuel tank. Last October I went to take her for a drive and the carbs were dry, the fuel filter was dry and I was scratching my head. Lo and behold through some sleuthing I discovered my original fuel line decided to make some ventilation holes. 55 year old lines finally met their death. I was going to patch it...then i thought...order new stainless lines but I wanted to make the slow shift to EFI and decided to go with 3/8" stainless lines over the factory 5/16" lines. I bit the bullet and talked to the guys at Tanks Inc on recommendation of AlexP(plus he is my cousin) as he used them for his Roadrunner GenIII setup. I ordered up two 3/8" lines from InlineTube with the chassis clips to go along. EFI Tank from TanksInc, reed style float to feed the signal to the factory dash gauge which hasn't seen any use since it was restored ten years ago and the fuel sending unit transmitter was Chinese trash. Always guessing how much fuel I have in my tank. I had retrofitted an Autometer float to a factory sending unit and added ANOTHER gauge to my setup which was annoying, now that gets removed. I purchased the 255LPH sending unit from T.I. and the carb kit install. A few AN fittings and a fuel pressure regulator to kick the 100psi down to 7psi. No instructions in the box so thats going to be interesting, hopefully their website has something. It really is a nice tank, I am going to use my original straps with some rubber padded strips to prevent metal to metal rattling on the mounts. The original tank weighs 16.5 lbs and the new tank weighs 20.5 pounds.

First question is what to do with the tank vent. The tank itself has one, they supply a Y fitting to connect to the vent on the fuel pump plate which. They also supply a ball valve aerator (venterator?!?!) which says it should be mounted at the highest point vertically. Since I have the Fuel fill tube vent on the 69 Charger feeding off a port on the fill neck, do I have to install any of the aforementioned since the exit of the fill tube vent releases vapor through the floor?

Next question is: Where is a smart place to connect the fuel regulator. I see people insytalling it in the engine bay on the radiator support and I can't help but think that if a hose bursts that pressurized fuel is a great way to ignite on the exhaust. I was thinking to mount it on the subframe near the fuel line, with a debris cage around it just in case a fuel line lets go, it will be spraying on the ground below. I don't like running braided hoses for fuel line nor rubber hoses for more than 6 inches. The previous Edelbrock fuel pump was hard lined to my CH28 with an inline psi gauge. I already installed the block off plate from Summit, where even though it was stated to fit RB blocks, it wasn't. Had to take a grinder to the edge facing #2 cylinder

Few pics of the tank as well as the vent plate from above

No mention of what EFI system you're using, that will play into the rest of the components.

I'm installing a Holley Terminator Stealth - not that I care about the "Stealth" part !! I'm using this fuel log with integral pre-set regulator. So no worries about where to mount it.

Right now it's going to be feeding my CH28 Dual Quads until i can scratch up the coin and migrate to the Edelbrock Pro Flo 4 XT. I love the aggressive look of the runners and it'll match with the rest of my top end since I'm running performer RPM heads.

For the tank vent it just needs to be higher than the tank. I run a small K&N air cleaner on the end of mine, and it is mounted in the rear axle hump, Mine is an Ebody. What size hoses are you using for feed and return lines? I run a 3/8 feed and 5/8 return, no starvation issues so far.

This is my system.

Converting to EFI?

The setup for my 51 Plymouth's flathead

5/8” return ?!?!

I asked TanksInc and they told me to run dual 3/8" supply and return. I'm wrestling the fuel line out right now because i have welded subframe connectors. Good idea on the K&N filter. I could probably feed something similar through a PCV filter in the same area. I don't want to run it into the trunk because vapors travel

What you need is enough of a return line size to not show any pressure on the return line. If there is any pressure there it messes up the pressure at the injector and throws off the calculations. So yeah, 5/8" will do the trick, but is most likely way over kill. Generally, same size as the supply or one size smaller is more than enough. This also assumes consistent sizing throughout the return line and no kinks or real sharp bends.

When I converted my Diplomat over to EFI I used the original supply line, 5/16", as the EFI return and bent up a new supply line, 3/8". If there is a premade OEM supply line available you can use that as the return.

I added a nipple to my stock sending unit to tie into the new return setup

For the vent, I placed mine in the highest point in the filler neck with a vented cap.

If you are making over 600hp that well inside the tank will get sucked dry, speaking from a hard lesson in life experience .

Yeah i just purchased two stainless ⅜" lines..pre-bent to replace the original factory lines.

I saw the other post on here with the 3/8” hole that was .050" off the bottom of the tank and the attempt to make that orifice larger to show more fuel to fill the well and avoid fuel starvation. I'm still around 490ish to 500hp. I think I'm safe for now with the 440. If i build my 505 then surgery will have to be performed on that tank but cross that bridge when that day arrives. I appreciate the heads up on it though 👍🏽

Can i ask where you placed the fuel pressure regulator?

You are going to need to think carefully about the fuel regulator since you are planning to run carbs and then switch to EFI. You can buy a fuel regulator which comes with two springs so you can switch it from being a low pressure regulator to a high pressure regulator but they are expensive. You can also just buy a carb regulator now and then replace it with an EFI regulator. Same thing with your fuel lines. For EFI you only need a single 5/16 pressure line. Put the regulator and the pump inside the tank and then run a single pressure line up to the throttle bodies. But that doesn't work so well for carbs. With carbs you typically want the regulator up front and fairly large lines since the fuel only has low pressure on it.

In short, EFI is plumbed differently than a carb so you either need to do the job twice, or you need to accept some compromises.

i have always used the same size supply and return lines as recommended by most fuel system manufacturers. On the pump / regulator issue, I'd be a bit concerned about throttling a high PSI pump down that far. I'd suggest a lower pressure version of the same pump and swap it out when you make the switch

I already purchased the TanksInc carb regulator. It's external. I didn't want to mix and match and find out one product from one company won't be compatible with another. This is their system fully so if something needs to be diagnosed it's a phone call and and an answer instead of "well you need to contact xxxxx"...I live in Europe, i waited 3 months for these parts to arrive. I am a turnkey guy. I just wanna drive my car with reliability not tinker with it on the side of the road 😂.

Below is the regulator. When i make the switch to multi port injection, all i have to do is swap out the regulator, feed the rails and put the carb regulator on eBay and make 25% of my money back

I've gone the other way on a couple of late 80s trucks with that horrendous TBI system those had, went from that to Edelbrock 4 barrel carb and,4 pin Mopar ignition box

Yes, I mounted it on the firewall, passenger side by the heater fan. I placed it after the fuel rails so the injectors get all the fuel from the pump, I run 50 psi. My 440 has 500 hp, and starvation has never been an issue.

I'm mostly looking for drivability. I have spent enough coin doing the dual 500 Edelbrock and CH28. I'm happy with it for now as a system which is why i just realized to deliver pressurized fuel to the engine bay. I have killed 2 batteries and a fuel pump trying to get her started. Who knows if or when the ProFlo will go on.

How can i make these flares for the fuel lines? I think i need to edit my fuel line because I'm running subframe connectors and i need to make a splice since i can't eat the pipe into place like factory. My flaring tool is for 37° conical breaker lives and i think doing that for fuel line with a rubber hose offer the connection is going to cut the line. I'm looking to make this type of connection below.

I already cut a 1/2" hole into my subframe and placed a pipe in to weld up and strengthen the passage. Also below

I was today years old when i found out it's called swaging

Not exactly the same but i always just did the first step of a double flare, but not mashed completely.

been doing that for 45 years

Had a few days off from work and turned the wrench a few more times on her this weekend.

Got the reed float and the fuel pump installed. Bench tested it wet and all works there. The sleeve was interesting to slip over the pump. Used long drill bits to reduce the surface tension and enlarged the sleeve. Slipped right in. Installed weather-tite connections on everything but decided to just use blue 12v male/female terminals so there is more surface to carry the amps. Soldered everything, heat sink, etc.

Painted up the fuel tank straps and added insulation from my drywall 😂.

Started installing the fuel lines but i forgot about the weld-in subframe connectors. That was a PITA. opened up the subgenre and welded in an oversized pipe so i can maintain a rigidity.

Have a few more connections to make where I swagged the pipe
Ran out of hose clamps.
Next up is the electrical, I am trying to source a relay/fuse box so i can make a cleaner install of everything aftermarket in my ride. Local shops don't have anything helpful 🫤

EFI is a sweet upgrade. Check out Marine electrical components. I find them to be of higher quality in general. West Marine is one of dozens of places that sell really cool relay and fusing components.

What your doing in your part of the world must be very challenging and a lot harder "running out of those clamps" than doing the same conversion here in the U.S.
Good on You

You'd be amazed. Finding things that fit is a bit tough but i have some tools that i can modify parts. I found a few guys that i can call and we can source or fabricate what we need. Ordering parts takes about 3 months for large items. With a few guys that I know and what we're working on we usually put a summit order all together so it comes in one box and we only pay customs tariffs once.

I wasn't happy with the vent tube. Looks something that backwoods guys would do. Got some black tubing meant for ether and made this below today. It's going to continue on towards the filler neck tube and I'm going to step it down to an 8 mm with a brass T and join it up to the factory vent.

Trying to find time between work and social life to work on her. Tried locating 3/8" stainless fuel line which is daunting. I only need a 3' piece. Most guys here just run rubber tubing from front to back but that's cheesy to me. Great way for dry rot or worse...a rock

Actually, stainless can be susceptible to work hardening, depends on the type. Which means a rubber hose could be more durable in the long run.

https://www.cnccookbook.com/work-hardening-strain-hardening-machinists-guide/

But proper mounting of the SS line fixes that concern.

not trying to be a smart a$$, but if it were me, i would use fuel injection clamps on the plastic tubing on your tank instead of the worm clamps shown in the picture.
those are a 360 degree clamp, would seal better, and wouldn't dig into the plastic line like the worm clamps shown could possibly do.
just my opinion, so please don't take offense.

What are "fuel injection clamps" ???

they are a "band style" clamp with a single bolt you tighten until the opposing ends touch.

example : https://www.ebay.com/itm/204427584383?

A stainless guy HUH??? Ever heard of Swagelok fittings? they are far superior to the crap earls and oter supplier push off on people. Google them
and BTW I happen to have a 50 ft. roll of 3/8, 316SS instrument grade tubing along with a good assortment of Swagelok fittings in various sizes up to 1/2 tube. Most are 3/8 with a few 1/4". PM me if interested as I no longer have a need for either.
an example of the tube & fittings in the pic

It sure is pretty but I live in Greece. I haven't driven my car since last November. I was the guy using bending tools and double flares with brass tees and NPT fittings. I bought the pre-bent 3/8" lines from inline tubing. I bought stainless clamps and those are going on. I bought insulated cable clamps. I wish i could call Summit and order things at random . I used to live down the street from Earl's and they would help me out. I have medical grade stainless on order through a friend as we speak and its $130 for 10 feet of tubing because I want to make some unforeseen bends because I forgot I had subframe connectors welded in.

The wrap around hose clamps might be a nice addition. i will see if I can source them locally but every shop I have called forparts has told me "everyone just installs kevlar (or braided) fuel hose...just use that. Thats the hokey way. I like metal. As for the AN fittings, yeah, they are expensive. I just paid $200 bucks for 7 fittings so I can finish the job and hopefully get her on the road soon. Summer is here and I need to burn my wallet on fuel.

The Swagelok fittings look nice. again, I live in Europe...I am just happy I found a place with Army Navy fittings 30min from my house. It took me 4 days of finding a swag tool so I can flare out the ends of the pipe and give the hose clamps something to prevent slipping off.

it's just a vent tube. Nothing to be alarmed about. I heated up the ether tube and slipped it over. The one fitting is push-lok and doesn't need a clamp. What I did was overkill

What's the point of "medical grade" ??

It's not cheap chinesium crap that'll rust.

sorry for the confusion on my part.

So I needed some extra AN fittings for my installation to make it a lot less painful. I'm lucky that even in Greece there is one shop that imports fittings from Australia. 30% higher cost but what are you going to do. I got the regulator installed on the frame rail up front underneath the number two cylinder as low as I could possibly get it. It's out of sight there's no gauge on it and it's there if I ever need to adjust it which is one of my questions in a little bit. I accidentally kinked my return pipe even though I was using the proper tool and I took it to a buddy of mine who cut it off and tigged on a new corner and then pressure tested it to 150 psi. From what tanks told me it's only going to need two or three PSI from the regulator. Instead of installing the slip-on fittings with a 4 inch long and 2 inch wide fuel filter I went ahead and put a 2inch -6AN stainless steel mesh filter right in front of the fuel tank and hooked it right up to the stainless pipes with two inches of rubber hose. I was getting iffy coming close to today because I had to start her up for a car show tomorrow. Spent all day doing electrical. Everything is grounded everything is soldered on with heat sink. Unfortunately one of the problems is that even with the new float style sending unit rated at 73-10 ohms it reads correctly at the sending unit but the gauge up front even though it was professionally rebuilt by Gentry at Auto instruments, with a full tank of fuel I'm only getting at most 3/4 on the gauge. The gauge has never been operated until Tuesday. I was using an Autometer fuel gauge and float and even that broke down. I ran another cable to replace the factory cable but I haven't installed it yet I'm expecting resistance on the copper. Maybe it's an old cable. I don't honestly remember if we replaced that cable when we restored her almost 25 years ago. Wow 25 years ago. That really makes you wonder. and I'm going to replace it eventually and hopefully I can get a full reading on my gauge. Under the good stuff I haven't started my charger since October. I turned the key and prime the system and saw the gauge on my supply of the Dual quads come up to 10 psi which I promptly lowered to 6.5 PSI. I turned the key for 2 seconds and she kicked right over. My mind is blown. I wish I did this upgrade years ago. I have killed two batteries in one month using a mechanical 120 GPH pump trying to get her started. Spraying fuel down the venturis, getting aggravated and walking away. And here I am 8 months later with two seconds of the key and she kicks over just amazed.

zeQuestion now

I took her out for a drive just now and even though I haven't hooked up my air fuel meter to my bung I can feel that there's a little bit decrease in performance. I'm guessing that's because of 6.5 PSI. Being that I have dual 500 edelbrocks and the 3/8 supply tube. Should I increase my PSI to 7.5 because I'm feeding two carburetors?