Fuel system issues

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805moparkid

805moparkid

Slant and AFX Guy
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ok so was messing with the dart today! i installed the holley red pump that MARK ETHERIDGE (MadMax/6) sent for an Xmas present!

anyways... i up jetted like at the track (69/75) and removed the air cleaner and went for a ride...

well instead of it starting at 5400 it is now at 5800 in second, nothing in first...

so i borrowed my bosses remote fuel pressure gauge, drilled the rail out to 15/64's (there wasn't enough meat for 5/16) and drilled the fuel inlets to 5/16. lastly the 3/8 inlet is only a 5/16 so i think that might be the issue... so im looking into a new rail...

so i went for another cruize...

so with the engine off the pressure was 6psi steady
with running it was about 8psi
driving down the road normally it was from 8-9psi
on full throttle run it went from 9 down to 6 at the launch, then back up to 8, i short shifted 1st cuz i was focused on the fuel gauge, in second it dropped to about 5 or 5.5 in the middle of second and slowly climbed till i shifted again where it was around 7 again...

sorry for the long post lol... but im gonna look into a new fuel rail and should be done with the issue...

here is the rail i was looking at...

http://www.summitracing.com/parts/SUM-220106-B/
 
That is the one I used on the 340 and use on my 416. What you may have is a restriction between the pump and the fuel pressure regulator. My fish still has the stock fuel line between the fuel pump/filter and the regulator but the car does not seem to run out of fuel on a good pull like the end of a track run. yeah, the AN6 line is sitting on the workbench ready to install to replace it. My fuel pressure gage is on the regulator under the hood so no real idea if the carb is getting starved at high power or not. It may be and that is why the larger fuel line will be going in. The dyno sheet shows about 40 GPH at 6000 RPM which I KNOW that little line will not support since I tested the flow in the shop and it is just under that.

<well instead of it starting at 5400 it is now at 5800 in second, nothing in first...>

That isn't making sense... do you mean started missing or something?
 
airwoofer said:
That is the one I used on the 340 and use on my 416. What you may have is a restriction between the pump and the fuel pressure regulator.

not running a regulator, and do you mean you used the new/old fuel rail/pump??

i have all new lines, pick up, and sock (3/8)

<well instead of it starting at 5400 it is now at 5800 in second, nothing in first...>

That isn't making sense... do you mean started missing or something?

it started "shooting ducks" at 5400 with the old pump and un modded fuel log, with the holley red pump and the rail drilled out to as far as it can go (15/64's) it started at 5800...


hope that helps

racerhog said:
I thought the Holley red pump was only good to 7psi Max.......
Click to expand...

2x...
Click to expand...
 
Total timing ok?

Carb Float level ok?

3/8 line should be good to support your 6 ?

Wheres your build posted at so I my take a look at it?
 
racerhog said:
Total timing ok?

Carb Float level ok?

3/8 line should be good to support your 6 ?

Wheres your build posted at so I my take a look at it?
Click to expand...

timing is 30* all in

just barely a trickle of fuel with the plugs out

3/8 is plenty but i think the rail is the issue so i have a new one on order...

http://www.forabodiesonly.com/mopar/showthread.php?t=128702

airwoofer said:
With an elec pump why are you not running a regulator?
Click to expand...

i figured since im not bouncing the float off the seat it wasn't an issue...
 
Run your floats up a little. About halfway up on the plugs.
 
Hum..... Dose this car still have points in it?
I see the Blaster Coil. But I'm just checking..
Might try an #80 jet out back..
Take a look and see if that carb has Fast fill needle and seats? 80's 90's 110's?
But I really think as long as theres not a bunch of 90* fitting in the system. I think it should be good enough.

http://www.holley.com/types/Needle and Seat Assemblies.asp

Just food for thought....
 
racerhog said:
Hum..... Dose this car still have points in it?
I see the Blaster Coil. But I'm just checking..
Might try an #80 jet out back..
Take a look and see if that carb has Fast fill needle and seats? 80's 90's 110's?
But I really think as long as theres not a bunch of 90* fitting in the system. I think it should be good enough.

http://www.holley.com/types/Needle and Seat Assemblies.asp

Just food for thought....
Click to expand...

it has a petronix ignitor II that i had tested when the issue started... not spark scatter untill 8900rpm lol...

so far before the fuel issue it ran its fastest with a 71 with pv installed/73.

and i have no idea if it has fast fill seats or not... its a 4150 holley 600 DP
 
You seem to have at least one other thread on this problem: http://www.forabodiesonly.com/mopar/showthread.php?t=168274 It's probably why there's some confusion here.
As I remember the Holley red pump, it's not supposed to have a regulator. It has a weaker relief spring than does the blue pump, which requires a reg.
You don't mention volume. You can have NO volume (flow) and still have pressure.
On a lower (relatively) hp engine that has a Holley carb, those two big fuel bowls should be enough to keep it running for a while even if you have no flow. Fuel line size shouldn't be a problem at your power level.
I think you need to check fuel volume. See how much pumps into a pan. -I don't remember the requirements, I'm sure others can help.
If your volume is good, I'd look at the ignition. As an example; when the distributor cap on my boosted (7#) 5.0 gets old, it breaks up at higher rpm's. Ignition problems can be anything from a bad ground on up. Check the cheap stuff first. And consider any aspect of it.
Excuse me if I'm out of bounds here, but I hope madmax/6 doesn't mind you publishing his entire name for the entire world to see!
 
SpeedThrills said:
You seem to have at least one other thread on this problem: http://www.forabodiesonly.com/mopar/showthread.php?t=168274 It's probably why there's some confusion here.
As I remember the Holley red pump, it's not supposed to have a regulator. It has a weaker relief spring than does the blue pump, which requires a reg.
You don't mention volume. You can have NO volume (flow) and still have pressure.

yes that was a thread i had up...

as to the pump it came off an 11 second slant car and right on to mine so im not worried about the pump.

On a lower (relatively) hp engine that has a Holley carb, those two big fuel bowls should be enough to keep it running for a while even if you have no flow. Fuel line size shouldn't be a problem at your power level.
I think you need to check fuel volume. See how much pumps into a pan. -I don't remember the requirements, I'm sure others can help.
If your volume is good, I'd look at the ignition. As an example; when the distributor cap on my boosted (7#) 5.0 gets old, it breaks up at higher rpm's. Ignition problems can be anything from a bad ground on up. Check the cheap stuff first. And consider any aspect of it.

well the issue got better with the new pump and almost went away with the mods to the fuel rail so im just gonna get the new rail and re-check fuel pressure on a run...

Excuse me if I'm out of bounds here, but I hope madmax/6 doesn't mind you publishing his entire name for the entire world to see!

his name is no secret to us slant guys so it shouldn't be an issue...

racerhog said:
So Jetting it down you think is causing it to back fire out the exhaust?
Click to expand...

no... when i first put the 4.88's and went to the track i couldn't get past 5500 with out it popping really bad... so i jetted up 2 to see if it helped and it got worse/lower rpm...

so my thinking was that bigger jets = more fuel sooner = no fuel in bowls...
Click to expand...
 
He's posted step by step what he did. He went to a steeper gear and started shootin ducks. That aint ignition. That's fuel. He even has said he fattened it up and it helped. He made FUEL mods and it helped even more. IT'S A FUEL PROBLEM. His little slant is just suckin that 600 slam down is all the problem is. It's a lot hotter than some of yall think it is. I think in the end, it's also gonna need more carburetor. You watch and see. It's a frikkin race car for God's sake. It ain't like he's goin to buy groceries in the thing.
 
I,Mark Etheridge do not mind Ed posting my name.I ran that pump tru a regulator at about 5.5lbs.and ran a 11.43 with my slant,no fuel starvation.I agree with most of you,its not fuel starvation related.I dont think bigger rails will change a thing.Float level possible????I lean more towards ignition issues.Just my thoughts.And the only reason I changed out pump is cause I am going to spray my car,60 shot, to try for 4 more slant records.Mark Etheridge
 
madmax/6 said:
I,Mark Etheridge do not mind Ed posting my name.I ran that pump tru a regulator at about 5.5lbs.and ran a 11.43 with my slant,no fuel starvation.I agree with most of you,its not fuel starvation related.I dont think bigger rails will change a thing.Float level possible????I lean more towards ignition issues.Just my thoughts.Mark Etheridge
Click to expand...


well it sure got alot better when i installed your pump, and almost went away with drilling the rail out... so i gotta think its fuel...

dizy was spun to 8900 before it broke up... i have a new blaster 2 coil and 8.5mm wires less than a yr old on it...

would like to do a MSD 6al on it though
 
Ya owe nothing.When you bought that relay and fuses,and wouldnt except payment,that told me you were a giver.I give to givers.How come I cant spell givers right?Doesnt look right.Mark
 
madmax/6 said:
Ya owe nothing.When you bought that relay and fuses,and wouldnt except payment,that told me you were a giver.I give to givers.How come I cant spell givers right?Doesnt look right.Mark
Click to expand...

awe.. what a bud...

hey did you see my post on MATs hotel cost??
 
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