Complete fuel system

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DentalDart

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Ok help me come up with a game plan. I want/need to start buying parts…

motor 400 currently…
727 transmission

No fuel tank, no fuel lines, no fuel pump, no carb…

I have stock parts in my purple 340 car, with 750 brawler. Works well, except for if you try to start it 15 minutes or so after you drive it, the starter has to crank a bunch because it has to get fuel back to the carb. Maybe it’s a lack of tuning as well…

Do I run stock parts again like tank, fuel sender (most are crap?), 5/16 lines and then 750 DP. or do I do an efi tank with carb like on the MotorTrend build. https://www.motortrend.com/articles/mopar-a-body-efi-fuel-tank-conversion-cpp/

Thanks
 
Works well, except for if you try to start it 15 minutes or so after you drive it, the starter has to crank a bunch because it has to get fuel back to the carb. Maybe it’s a lack of tuning as well
Next time you think it's going to be hard to restart pull the air cleaner, and look down the carb pump the throttle a couple times

If the accelerator pump shoots fuel it's not a fuel delivery issue.

It might be how you are trying to start it. Are you pumping it 4 or 5 times then cranking?

Typically when hot 1 pump is more than enough.

More could be flooding the intake.

If I drove my dart yesterday 2 pumps the next day and it fired up fine.

Drive, shutoff, 15 minutes later no pumps restart no issue.

The fuel does not get pulled out of the carb, if it is super hot it might boil dry but that's another issue.


As to your question.

Stock will give you the best chance of not having issues, ( electrical, fuel pressure, replacement parts)

BUT...

An EFI tank and quality EFI are very tempting! And that's coming from a stock is the best guy.
 
two schools of thought: do you want to KISS and roll or are you thinking long term and want to "future proof" the car?

on the cheap i'd just grab a tank that's in the $100 range (probably a spectra) and a spectra pick up (i've had decent luck with these) and then get the good seal and lock ring from DMT and ship it. bend up some line or hit up inline and order the kit and call that part done. figure out a pump and you're squared away there. reuse your brawler and just get it tuned in right.

however, if you're thinking more power down the line and fuel injection, i'd just push the easy button and order up an EFI tank from tanks inc and get the corresponding sending unit for the gauge and the regulator kit for a carb engine. the wiring is dead simple and if the pump craps out it's a popular piece that you could get at a parts store and swap if need be. then if you wanna switch to EFI later you just need to change out the regulator.

all of it kind of hinges on what direction you want to take the car and how much money you want to spend along with what are your feelings on regulators and electric fuel pumps and assorted wiring.
 
Replacement stock parts can serve you well and will be reasonably priced. You might find everything used.
 
EFI tank, regulator for carb and some 3/8-1/2 lines running a return.

This would be my setup if I had to do it over again. Currently running stock tank, Walbro fuel pump, 3/8 fuel lines with brazed 3/8 return to the factory sending unit. Never have an issue with restarts, even in 100+ temps in CA.
 
Next time you think it's going to be hard to restart pull the air cleaner, and look down the carb pump the throttle a couple times

If the accelerator pump shoots fuel it's not a fuel delivery issue.

It might be how you are trying to start it. Are you pumping it 4 or 5 times then cranking?

Typically when hot 1 pump is more than enough.

More could be flooding the intake.

If I drove my dart yesterday 2 pumps the next day and it fired up fine.

Drive, shutoff, 15 minutes later no pumps restart no issue.

The fuel does not get pulled out of the carb, if it is super hot it might boil dry but that's another issue.


As to your question.

Stock will give you the best chance of not having issues, ( electrical, fuel pressure, replacement parts)

BUT...

An EFI tank and quality EFI are very tempting! And that's coming from a stock is the best guy.

drove my car yesterday, not today. After reading this, went out 0 pumps and car started right up.

If I drive it right now, get it hot then let it sit while pumping gas at the gas station I have to crank it a decent amount before it starts, I then end up pumping it while cranking until it fires up, sometimes it fires faster when I hold the throttle down.

As for my original question. The EFI tank is very tempting but probably 2x the cost….
 
two schools of thought: do you want to KISS and roll or are you thinking long term and want to "future proof" the car?

on the cheap i'd just grab a tank that's in the $100 range (probably a spectra) and a spectra pick up (i've had decent luck with these) and then get the good seal and lock ring from DMT and ship it. bend up some line or hit up inline and order the kit and call that part done. figure out a pump and you're squared away there. reuse your brawler and just get it tuned in right.

however, if you're thinking more power down the line and fuel injection, i'd just push the easy button and order up an EFI tank from tanks inc and get the corresponding sending unit for the gauge and the regulator kit for a carb engine. the wiring is dead simple and if the pump craps out it's a popular piece that you could get at a parts store and swap if need be. then if you wanna switch to EFI later you just need to change out the regulator.

all of it kind of hinges on what direction you want to take the car and how much money you want to spend along with what are your feelings on regulators and electric fuel pumps and assorted wiring.

I doubt I’ll do fuel injection down the line but power is a definite yes.

Also looked at this, seems to be a drop right in.

https://www.holley.com/products/fue...cessories/muscle_car_efi_modules/parts/12-319
 
The EFI tank is very tempting but probably 2x the cost
But that's a 1 time in your life expense!


sometimes it fires faster when I hold the throttle down
That sounds like flooding.

Holding the throttle open is the cure for a flooded intake.

Thought ..

Next time you stop like getting gas, quickly hop out, remove the air filter and look for fuel dribbling into the intake.

It might be something as simple as a too high float?
 
3/8ths from pump to the sock in the tank. I ran mine inside the P-side framerail, into the area at the front perch of the rear spring. There I installed a life-time EFI fuel filter , then more hard line to the sender which I took apart and installed more 3/8ths hard line then a new 3/8ths sock. I joined the hardline to the sender with EFI rated hose and double-clamped it with gear-clamps. That EFI line lasted 22 years, with a steady diet of 87E10.
At the front, My engine is chained down, so it doesn't move much. There I pulled the line out of the frame, left a short gap, then an EFI jumper. From pump to carb is a one-piece isolated from the block, and not clamped to anything hot. Works great.

Now, as to your hotstart issue, this goes back to the transfer-Slot exposure underneath the primary throttles.
1) If you are running a lot of Idle-Timing, then to get the Idlespeed down, you will have backed the curb-idle screw out, which reduced the fuel coming from the transfers. In compensation, you had to increase the fuel coming from the mixture screws. At start up, the lack of signal to the transfers, means the engine will yank real hard on the mixture screws. And if there is any T-slot exposure at all, the engine will, yank air thru the slot, and dry it right up, in a heartbeat. But hang on, with the idle mixture screws set rich, your entire lowspeed circuit, when off-idle, will also be rich. That means, it was rich when you shut it off, and the still going up and down pistons, sucked a bunch of fuel in, until the crank finally stopped. If this applies to you, the cure is simple, just reset the Idle timing to 12>14, lean out the mixture screws to in the middle of their range, and increase the Idle speed with the speed screw, Badaboom, now the T-slot will quit early at shutdown, the Mixture screws won't get tugged on so hard, and the slots will probably hold some fuel for the next start.
2) if you are not running enough Idle timing, the opposite will happen.
3) when it is just right, and the guel level is where it is supposed to be, you should be able to, with the mini starter, reach in thru the open window, twist the key, and the engine will spring to life.

BTW,
it is a myth that more timing makes an engine easier to start. Once you have your engine set just right, do this; get a baseline by twisting the key and let it fire up on it's own, and make a note over the next say ten starts and record how many fails there were.
Next, reset your idle timing 5 degrees more advanced, and repeat, then repeat at 5 degrees retarded; then compare the failure rates.

The truth is this; and this is not directed at anyone specific, just a general "you";
I'll guess that unless your timing is locked at 35 degrees, ALL Hi-performance engines idle with retarded timing. My guess is that once they are idling, they will be most efficient at between 30 and 40 degrees.
But good luck driving away (unless you are running a Vcan on manifold vacuum). So ask yourself, if it wants say 35, and you give it either 12 or 20, how much difference is this gonna make , it's STILL retarded!
I really hate to say "trust me", but
if you are running 20ish degrees of Idle-Timing, just retard the thing to 12>14, retune it, and see what happens.
 
I doubt I’ll do fuel injection down the line but power is a definite yes.

Also looked at this, seems to be a drop right in.

https://www.holley.com/products/fue...cessories/muscle_car_efi_modules/parts/12-319
i'm not a fan of the sniper unless it's used as part of the entire system. with that, you still need a tank and you still need a regulator so basically you're getting a pump and a sending unit. and to my knowledge the holley is proprietary pump or at least the connections so if it craps out, you're calling them for a replacement.

the tanks inc set up gives you a serviceable pump, a baffled tank, your choice of sender.

you're going to need a pump and a pick up either way along with the tank, so why not choose something that is designed to work together.
 
3/8ths from pump to the sock in the tank. I ran mine inside the P-side framerail, into the area at the front perch of the rear spring. There I installed a life-time EFI fuel filter , then more hard line to the sender which I took apart and installed more 3/8ths hard line then a new 3/8ths sock. I joined the hardline to the sender with EFI rated hose and double-clamped it with gear-clamps. That EFI line lasted 22 years, with a steady diet of 87E10.
At the front, My engine is chained down, so it doesn't move much. There I pulled the line out of the frame, left a short gap, then an EFI jumper. From pump to carb is a one-piece isolated from the block, and not clamped to anything hot. Works great.

Now, as to your hotstart issue, this goes back to the transfer-Slot exposure underneath the primary throttles.
1) If you are running a lot of Idle-Timing, then to get the Idlespeed down, you will have backed the curb-idle screw out, which reduced the fuel coming from the transfers. In compensation, you had to increase the fuel coming from the mixture screws. At start up, the lack of signal to the transfers, means the engine will yank real hard on the mixture screws. And if there is any T-slot exposure at all, the engine will, yank air thru the slot, and dry it right up, in a heartbeat. But hang on, with the idle mixture screws set rich, your entire lowspeed circuit, when off-idle, will also be rich. That means, it was rich when you shut it off, and the still going up and down pistons, sucked a bunch of fuel in, until the crank finally stopped. If this applies to you, the cure is simple, just reset the Idle timing to 12>14, lean out the mixture screws to in the middle of their range, and increase the Idle speed with the speed screw, Badaboom, now the T-slot will quit early at shutdown, the Mixture screws won't get tugged on so hard, and the slots will probably hold some fuel for the next start.
2) if you are not running enough Idle timing, the opposite will happen.
3) when it is just right, and the guel level is where it is supposed to be, you should be able to, with the mini starter, reach in thru the open window, twist the key, and the engine will spring to life.

BTW,
it is a myth that more timing makes an engine easier to start. Once you have your engine set just right, do this; get a baseline by twisting the key and let it fire up on it's own, and make a note over the next say ten starts and record how many fails there were.
Next, reset your idle timing 5 degrees more advanced, and repeat, then repeat at 5 degrees retarded; then compare the failure rates.

The truth is this; and this is not directed at anyone specific, just a general "you";
I'll guess that unless your timing is locked at 35 degrees, ALL Hi-performance engines idle with retarded timing. My guess is that once they are idling, they will be most efficient at between 30 and 40 degrees.
But good luck driving away (unless you are running a Vcan on manifold vacuum). So ask yourself, if it wants say 35, and you give it either 12 or 20, how much difference is this gonna make , it's STILL retarded!
I really hate to say "trust me", but
if you are running 20ish degrees of Idle-Timing, just retard the thing to 12>14, retune it, and see what happens.

You lost me at… transfer slot exposure underneath primary throttles…. What’s a T-Slot?

Timing is 16 idle 36 all in, I pretty sure I run pretty lean, at least I did. I’ll play with it some. I need to change the oil in the car anyways.
 
i'm not a fan of the sniper unless it's used as part of the entire system. with that, you still need a tank and you still need a regulator so basically you're getting a pump and a sending unit. and to my knowledge the holley is proprietary pump or at least the connections so if it craps out, you're calling them for a replacement.

the tanks inc set up gives you a serviceable pump, a baffled tank, your choice of sender.

you're going to need a pump and a pick up either way along with the tank, so why not choose something that is designed to work together.

Gotcha, I was thinking the Holley was a simpler system to use if it just goes in a stock tank.
 
A friend has had nothing but issues with the Holley EFI in his 67 Dart. Sent it in for repair, still had issues.
 
You lost me at… transfer slot exposure underneath primary throttles…. What’s a T-Slot?

Timing is 16 idle 36 all in, I pretty sure I run pretty lean, at least I did. I’ll play with it some. I need to change the oil in the car anyways.
You need too research the T-slot to understand what it does. Lots of good info on the web.
As for fuel system factory style tank, 3/8 line to a good mechanical pump for a street car, -6 from pump to carb. simple.
 
If you go sniper, to make it work be prepared to follow instructions.

Hyperspark dist.
Coil
Holler ignition box
Proper wiring
Tank
Pump
Regulator

Getting a clean signal and proper grounding are a few of the challenges.

I followed the instructions and have no problems. For now.

If you cut corners with any fuel system you will have problems.

I have the first generation sniper stuff with some issues but once sorted, it’s just a throttle body system. Some argue, with very good points, that with stock you can get up n running if you have problems on the side of the road. It’s not for everyone.

That said, I never need to hit the throttle when starting, cold or hot.

I just perused the article and got to the part where they say you can change the pump without cutting a hole in your trunk floor. Uhhhh…yeah no. 67 fastback

image.jpg


image.jpg
 
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You need too research the T-slot to understand what it does. Lots of good info on the web.
As for fuel system factory style tank, 3/8 line to a good mechanical pump for a street car, -6 from pump to carb. simple.

I looked up the t-slot, that’s the little opening where the throttle blades are. A long time ago I had it adjusted properly and I’d say it’s probably not adjusted correct anymore

Drove the girls to get donuts. Fires up first crank when cold, at the donut store it seems starved for gas. Crank it a bunch give it lots of gas before it fires up.
 
If you go sniper, to make it work be prepared to follow instructions.

Hyperspark dist.
Coil
Holler ignition box
Proper wiring
Tank
Pump
Regulator

Getting a clean signal and proper grounding are a few of the challenges.

I followed the instructions and have no problems. For now.

If you cut corners with any fuel system you will have problems.

I have the first generation sniper stuff with some issues but once sorted, it’s just a throttle body system. Some argue, with very good points, that with stock you can get up n running if you have problems on the side of the road. It’s not for everyone.

That said, I never need to hit the throttle when starting, cold or hot.

I just perused the article and got to the part where they say you can change the pump without cutting a hole in your trunk floor. Uhhhh…yeah no. 67 fastback

View attachment 1716284971

View attachment 1716284972

Thanks for the information. I just want something that works, I don’t care if it’s stock or EFI. If it fires right up every time I will be as happy as husband who’s wife finally doesn’t have a headache…
 
every time
Its been good.....so far. but these efi systems are not tried and true (specifically the aftemarket deal here, Im not talking a throttle a factory throttle body setup). A very good argument for going mechanical fuel pump, carb and heart starting coil is that if you spend as much time on that (carb) setup as you would on an efi setup you will have those results. This includes maintenance of the system. I re-wired the car (mainly because i didnt have wiring when I got it, or rather anything dependable) and felt like I could take advantage of a freshly wired system to control fan/timing n all that. So I did it. I haven't done long distance travel to really put my kiester on the line. I may come up with an "oh ****" box to be able to convert on the side of the road if my confidence shakes.

$0.02

A wife without a headache would be a very good deal.
 
Ordered fuel line from tank to engine, tank straps… but no fuel tank yet because I’m still undecided.
 
Hey DD,
will you shoot a couple pictures of your engine bay? Its is for some eye candy but to also see the condition of the wiring and components as well. I think it puts the viewers in the drivers seat to weigh in on what they would do.

My feeling without seeing things is to run a stock system with a mechanical fuel pump and spend the money on a solid carb with the possibility of running a return line. If the car has the right feel/look I would look into a period "cool can" for some fun but really just taking a look at underhood temps and eyeing the fuel charge and whether the new fuel line is running through "hot zones" ie are you running headers? whats your running temp? what does it shoot up to when you stop?

I dont think you are cooking the fuel out or anything like that, Im really not that smart, but I know these guys love their pics and i believe it will lead you down the path of success when asking questions.

$0.02
 
Hey DD,
will you shoot a couple pictures of your engine bay? Its is for some eye candy but to also see the condition of the wiring and components as well. I think it puts the viewers in the drivers seat to weigh in on what they would do.

My feeling without seeing things is to run a stock system with a mechanical fuel pump and spend the money on a solid carb with the possibility of running a return line. If the car has the right feel/look I would look into a period "cool can" for some fun but really just taking a look at underhood temps and eyeing the fuel charge and whether the new fuel line is running through "hot zones" ie are you running headers? whats your running temp? what does it shoot up to when you stop?

I dont think you are cooking the fuel out or anything like that, Im really not that smart, but I know these guys love their pics and i believe it will lead you down the path of success when asking questions.

$0.02

This is a new build, has no wiring but will have brand new wiring harnesses. Has no carb, don’t know what to run yet. No headers, stock exhaust manifolds. Everything is and will be brand new.

IMG_1760.jpeg
 
This is a new build, has no wiring but will have brand new wiring harnesses. Has no carb, don’t know what to run yet. No headers, stock exhaust manifolds. Everything is and will be brand new.

View attachment 1716285963
Looks good!!
I would ask the guru recipe for a carb setup with return line. The in tank pump is more quiet which I enjoy.

So, if it were mine, and knowing the anxiety of an efi setup (even though I have had success with mine) I would do ......

tanks inc with in tank pump although I believe you will have to make an access panel.
-6 line to regulator with a return line so getting pump with nipple for that
do not mount regulator on fire wall
I like making fuel lines with AN fittings to run them as far away from heat as I can. This is the point where you can also avoid the exhaust in the rear of car.

If you decide to go efi in future you then just have to change pump and regulator. Also, I am not sure if you get the correct carb pump if it even needs regulation but a regulator gives you the opportunity for return line.

I am just spitballen here (because I haven't run this setup, someone here knows) a little but Im trying to think ....clean....coool...fuel. good atomization...feed that thing.

follow me?

Also, run the fuel line where? inside the frame rail? or outside....that is if you have subframe connectors and all that. Some say in a T-bone situation the fuel line being outside the rail creates a pinch and could be more fire prone.

Just some things to think about. you are smart. I think you will do well with just a little more info from guys that are having success with cool...clean...carb setups.

image.jpg
 
As far as carb.

I see the Holley HP getting a lot of play from David Frieburger on road kill and engine masters. Now he might be just advertising so I always suspect a conspiracy, but again, maybe put it on the list of “check it out”.

And hopefully someone will chime in with their recipe for this setup.

$0.03
 
Summit sells some nice fuel systems in a box under their brand. I've installed several and I like um.
 
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