FI pump in tank

Jengel451

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Hey all, I'm going to convert over to EFI and will NOT be using an inline fuel pump that is external to the tank. Been there, done that and learned my lesson.

Here's the question. I have a 68 Fury 2 vent tank. Has anyone done this conversion and if so, what did you do? Find a sender/pump "All in one" unit to put in? or did you do surgery to the tank and put in a top mount pump?

Looking for input before I go down the painful discovery path. Yes, I want to learn from others mistakes! ;) And yes, i'm converting that decision is in stone, you do you and I'll do me.

Thanks all,

Jim
 
I've never seen or heard of anyone making an in tank pump that mounts through the existing sender unit hole. That's a nice idea though! By design most in tank pumps are cylinders from top to bottom. This typically requires welding a lowered corner to the tank. I've also seen pictures of guys who have carefully peened down a section of the tank to accommodate the pump.
 
I've never seen or heard of anyone making an in tank pump that mounts through the existing sender unit hole. That's a nice idea though! By design most in tank pumps are cylinders from top to bottom. This typically requires welding a lowered corner to the tank. I've also seen pictures of guys who have carefully peened down a section of the tank to accommodate the pump.
I ran a Mustang Tank in the back of a D100. Holley 12-305 Holley OEM Style EFI Fuel Tank Modules | Summit Racing

Best case is finding something with the same bayonet mount dimensions and modify to fit the C Body tank. Worst case is going down the path you laid out.....I really don't want to......
 
Hey all, I'm going to convert over to EFI and will NOT be using an inline fuel pump that is external to the tank. Been there, done that and learned my lesson.

Here's the question. I have a 68 Fury 2 vent tank. Has anyone done this conversion and if so, what did you do? Find a sender/pump "All in one" unit to put in? or did you do surgery to the tank and put in a top mount pump?

Looking for input before I go down the painful discovery path. Yes, I want to learn from others mistakes! ;) And yes, i'm converting that decision is in stone, you do you and I'll do me.

Thanks all,

Jim

Out of morbid curiosity...what lesson did you learn?
 
Out of morbid curiosity...what lesson did you learn?
External pumps don't last, even when you mount them lower than the tank there is enough effort to pull that they will cavitate and burn up. Usually when you don't want it too. Unless you have a lift pump before it. That, and they are really freaking noisy on their own, add a lift pump and it's just obscene.
 
The death of any electric fuel pump is running them dry, even the OEM pumps.

I presume you have looked all through the Holley website on EFI pump variations. From the in-tank stuff to the reservoir/pump that is mounted in the engine compartment (using an existing mechanical pump as the lift pump to the reservoir/high pressure pump combo)? Or maybe it's Edelbrock that sells that item? Anyway, the real need to "cut the tank up" has diminished in recent years. Holley even has a new electronic module which takes the place of the old sending unit, sitting on top of the tank.

Back in 1973, the CA-spec Imperials had an electric booster pump which was inline between the tank and the normal metal fuel line. I have several friends with mid-'50s Buicks which employ such a pump, when needed, to thwart the evil vapor lock in slow traffic conditions, on trips. GM parts also sells an inline electric pump, which was the old lift pump for the diesels, with about 12psi pressure. No noise there, either. But you need something with about 55-60psi pressure to run an EFI system.

ONE good thing about the in-tank pump is that the fuel surrounding it serves as a heat sink, keeping the pump cool as it works.

BUT, with any in-tank pump, you need to forget about using the last 1/4 of tank capacity. Reason? The "low fuel" lights typically come on with 2-3 gallons of fuel in the tank. Now, think or how large the bottom of a fuel tank is, then consider how deep the fuel will be at the 3 gallon remaining level. NOT very deep, even with the big Holley intake filters in place. Most of the OEM in-tank modules have a round plastic baffle they sit in.

Plan your project well! Be brave . . . "cut once". Good luck.
CBODY67
 
I think that B body Holley drop in sending unit will work. Worst case you can also buy their 68-70 B body (non-Charger) tank and bolt that in as well, you’ll lose a couple gallons of capacity but it does bolt up.

Tanks Inc also has them for the 68-70 B’s that will fit our C’s.
 
I may have a path now. Looking at various Holley in tank pumps for other mopars, even A body. Since they are a pump/sender unit it would be WAY easier due to the same ohm range for the gauge.

I have to assume that the Bayonet would be interchangeable between all mopar units of the same year range for the late 60's and if that's right, then even if it's close to the right angle, would be easy to modify to get the pickup on the bottom of the tank.

Looking at the top of the tank to trunk floor clearance, the top mount option gets pretty ugly.
 
I am going to use one of those intank pumps in my Challenger. Run to a regulator and then carb.
 
I may have a path now. Looking at various Holley in tank pumps for other mopars, even A body. Since they are a pump/sender unit it would be WAY easier due to the same ohm range for the gauge.

I have to assume that the Bayonet would be interchangeable between all mopar units of the same year range for the late 60's and if that's right, then even if it's close to the right angle, would be easy to modify to get the pickup on the bottom of the tank.

Looking at the top of the tank to trunk floor clearance, the top mount option gets pretty ugly.
Update us on what you go with, what you had to modify, and how it works. I'm preparing to do the same type thing soon when I drop in the new engine being built currently.
 
Have some info. I bought a pickup/Sender for a 68 B Body for comparison. It's close with a small tweak I thin it would work so I decided to pull the trigger on a Holley in tank unit for 68 B body.

It seems like the B body tank may be a little deeper from the mount, maybe 1/2 to 3/4". The holley unit has a flex line to the pump and the hydramat has some flex too. I think this may be a good solution so far.

Sender.jpg
 
Have some info. I bought a pickup/Sender for a 68 B Body for comparison. It's close with a small tweak I thin it would work so I decided to pull the trigger on a Holley in tank unit for 68 B body.

It seems like the B body tank may be a little deeper from the mount, maybe 1/2 to 3/4". The holley unit has a flex line to the pump and the hydramat has some flex too. I think this may be a good solution so far.

View attachment 637288
I see a couple of interesting toys in the background there
 
Hey all, figured I'd give a bit of an update.

The 69 B Body Holley In tank pump does in fact work! Just a little bending of the hard line on the pump to make if sit on the floor of the tank, it picked up fuel with 1/2 gal in it. The down side is that the float is way off, I tried a few different things to make it work but gave up and just wen with what I have, full tank shows 2/3 full, when on E it has ~5 gals in it. Good enough.

I installed the Sniper 2 and today was the first time I got it out on the road. SO much better than the original Sniper 1, WAY WAY better. More power, smoother, easier starts etc etc.

My 383 is bascially stock, Mild cam, Weiand dual plane intake and HP exhaust manifolds into 2.5 inch TTI exhaust. I used the original 5/16 hard fuel lines from the rear up to the cross member, then went to a filter and then 3/8 soft line up the firewall to the TB, no return line since the in tank pump has the bypass. Zero issues. When kicking on the AC the sniper just handles the idle kick without any other connection to the AC.
 
I think that B body Holley drop in sending unit will work. Worst case you can also buy their 68-70 B body (non-Charger) tank and bolt that in as well, you’ll lose a couple gallons of capacity but it does bolt up.

Tanks Inc also has them for the 68-70 B’s that will fit our C’s.
you have sparked my curiosity, I have looked at the 68 B body(non charger) tanks on tanks inc and they look almost the same shape with similar sending unit/filler neck locations. I am in the dilemma of setting up a fuel pump system for my new engine currently being built and wanted to do an in tank electric system without a bunch of hassle hence the reason I have been watching this thread. I know tanks inc has a B body with the electric fuel pump already incorporated, are you fairly confident the B body tanks work ok? I measured an extra 66 fury tank I have and it looks to be the same basic dimensions, only about 3.5-4 inches narrower but tank depth and length are basically the same and strap mounting locations should not be affected by the slightly narrower tank. I have just been reluctant to pay $300-400 to test fit and find out it doesnt. lol
 
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