I am finally going to address the richness on my new 1906. I have moved to 14 champions to try to counter the fuel carbon and it is not happy. So, am looking at the calibration chart for this carb, which is neat. Shows the stock jets and rods and changes. I have ordered parts, should have ordered the kit, but oh well. Am going to change to the 1455 rod first which cuts both cruise and power a bit, and will use new 12 plugs as gauge. Of course, this engine should have about a 9 heat, so will work down. The carb comes with 101 mains, and will first try the 98 after the rods, and continue down until it is happy. It runs great, but carbons up the plugs badly....so help on the way. Not sure I will do anything on the rod springs as long as they pull down fully, not sure I need to go to that level of performance for my 60 year old motor....but we will see.
Edelbrock 1906 jetting
- Thread starter 66furys
- Start date
Uhm what engine? Maybe a hotter coil will help. Stock Mopar are 28KV
With respect to metering calibrations, you can look in the FSM for the jet and rod sizes of an OEM carb for your engine. 440s had different jets than 383s did. BUT look at the jet size minus the rod diameter (one diameter for "cruise" and a smaller diameter for "power" sections of the rod).
I doubt the power valve spring will need any attention, for your application. The springs are colored and should have what their vac levels are in the Edelbrock carb tuning manual. Normally, the "power mixture" comes in at vac levels below 5.5"Hg, Vac levels above that should be on "cruise mixture". FWIW
Other than rods and jets, there is ONE other area that is a calibration point . . . the idle and main system air bleeds on the top of the venturi cluster (at least that is where they were on the OEM Carters). A smaller air bleed diameter will richen the circuit, as a larger bleed hole will lean it. The small hole is for the idle circuit and the larger hole is for the main circuit.
Please keep us posted on your progress,
CBODY67
I doubt the power valve spring will need any attention, for your application. The springs are colored and should have what their vac levels are in the Edelbrock carb tuning manual. Normally, the "power mixture" comes in at vac levels below 5.5"Hg, Vac levels above that should be on "cruise mixture". FWIW
Other than rods and jets, there is ONE other area that is a calibration point . . . the idle and main system air bleeds on the top of the venturi cluster (at least that is where they were on the OEM Carters). A smaller air bleed diameter will richen the circuit, as a larger bleed hole will lean it. The small hole is for the idle circuit and the larger hole is for the main circuit.
Please keep us posted on your progress,
CBODY67
Mine is the 383 and had an afb, original vintage, when I got it. I have recently pulled the mains and rods to measure, and they are smalllllll. Mains about 88 and rods about 58 x 50, under the corrosion and wear, so may not be right. But, the Edelbrock has much larger stuff as center....although, right on the restricted area around the rods. I searched the site for work on jets and did not find much, so thought I would just jot it down as I go for future. Good point on the air jets....had overlooked that.
Thanks for the reply and information.
I KNOW the 1966 Chrysler factory service manual has the carb specs I mentioned, plus illustrations of the idle and main fuel circuits. I would suspect the similar '66 Plymouth FSM would be similar. The jetting on the 440s is richer than the 383 jetting. As the Edelbrock AFB is jetted for "all", it would make sense it might be toward the "larger engine" side of things.
Still., I would compare the E-AFB jets and rods to what the OEM items were, using THEM as a guide on how to proceed and possibly where to end up.
The jets should be clearly marked/stamped with their size number on them. The metering rods will have a "dash number" on their upper areas for the same reasons. Using a chart, the power and eco diameters can be determined.
In the S-A Designs book on Rochester carburetors, there is a metering orientation where the diameters of the jets minus the diameters of the metering rod segments (AREAS of each, rather than just diameters!) are used to determine how far to go with each one in the quest of the "best calibration". Which is also MORE accurate than just doing simple match (subtracting). Itr would be logical to use the simple match (subtraction) to get close to a final sizing, but it is the DIAMETER numbers that get things much closer, for example.
In the end, I don't know that "re-invention" is needed, but fine-tuning things would be more appropriate.
Please keep us posted on your progress,
CBODY67
I KNOW the 1966 Chrysler factory service manual has the carb specs I mentioned, plus illustrations of the idle and main fuel circuits. I would suspect the similar '66 Plymouth FSM would be similar. The jetting on the 440s is richer than the 383 jetting. As the Edelbrock AFB is jetted for "all", it would make sense it might be toward the "larger engine" side of things.
Still., I would compare the E-AFB jets and rods to what the OEM items were, using THEM as a guide on how to proceed and possibly where to end up.
The jets should be clearly marked/stamped with their size number on them. The metering rods will have a "dash number" on their upper areas for the same reasons. Using a chart, the power and eco diameters can be determined.
In the S-A Designs book on Rochester carburetors, there is a metering orientation where the diameters of the jets minus the diameters of the metering rod segments (AREAS of each, rather than just diameters!) are used to determine how far to go with each one in the quest of the "best calibration". Which is also MORE accurate than just doing simple match (subtracting). Itr would be logical to use the simple match (subtraction) to get close to a final sizing, but it is the DIAMETER numbers that get things much closer, for example.
In the end, I don't know that "re-invention" is needed, but fine-tuning things would be more appropriate.
Please keep us posted on your progress,
CBODY67
The WAR goes on. For note, my AFB parts were old enough that the marks were gone.....I looked at all four parts, then measured each. But, got my new first try on jetting done on mine. The mail lost my first choice, the 1455 rods that would lean both cruise and power. So, I went to stage II, the main jets. I replaced the Edelbrock center point, the 101 with 98's. After my old hands fought over the small parts, I started him up. The idle was low, maybe leaner, but then I noted that the fuel filter was not filling, just gurgling. Cussing the new pump, I crawled under. The fuel line is now crap and leaking. Fuel line from auto parts about two years old now, leaking and I am sure drawing air. I think I have some very heavy Evil Energy line, and will replace. But this has been and continues to be two steps forward and three back. Here is hoping for some blessings and not curses. The engine is very responsive at the halt, and next will be some driving and install a test plug to see what we see.
My Fury had three sections of rubber fuel hose, a very short one at the tank, another short one at the front subframe, to connect to the hard subframe line, and a longer, ten inch or so piece to the pump. The one I mentioned above was the long one at the pump, now replaced. It was totally cracked up front to back....awful....an auto parts piece. I am going to replace others with Gates line in future. I checked the subframe piece....OK so far, now need to climb under an look at the tank section next....still not pumping properly. But, for sure, the front line was cracked and leaking....prob made in You Know Where.
Sorry, got off topic. I wanted to make a note on setting float height on the Edelbrock AVS. Both of my floats were a bit low and the drill was not close to the float, and one was way off on drop. So, in my eagerness, I just used my fingers to bend the float tab....bad juju. I way over did it the first time. So, a caution here. Use needle nose pliers to grab the tab, and very gently feel a bend by pressing on the float....easy, it only takes an RCH to move it. Also, do not try to change the drop until you have the height set, then gently bend the tang....gently.
So this small battle has not ended yet. The two small sections of rubber fuel line were not leaking....did not seem to be cracked as far as I could see. So, not enough fuel to the filter. This leads me to think that either the new pump aint pumpin, or the cleaned and coated tank with new sender and pickup aint pickin up. Letting the beast sit for a few months has not been kind to me.....under the car boy.
1970FuryConv
Old Man with a Hat
I would replace the fuel filter, 1st. If it's gurgling that could indicate a problem. NAPA 3032 is 5/16 line and good quality. It has an arrow on the side because it is one-way.
I would then disconnect the fuel hose at the carb. Hold the fuel hose in a jar. Have an assistant turn the ignition key and crank the engine over, while you see if you get repeating healthy squirts of fuel. Not a steady stream. Those healthy squirts mean the fuel pump is OK.
On terminology, a fuel line is metal, a fuel hose is rubber. If you call hose "line", you confuse your readers. Good luck Mopar Brother!
I try to use the right nomen for parts, and have lived a life on mechanical crap, from submarines to cars to bikes to tractors, an on it goes. You are right about the line and hose. Never thought of that point. As I then went back to drive the car after the rejet, it would not run. Or it would start, not idle at all, and was rough at higher revs....felt like a dead miss causing this mess, although normally a miss is not so bad, may just put you down on power. But not this time....I have never come across a condition like this....figured the new jets were not the issue, and thought electrical. So, back to the jump with plugs, check wires and cap, go into distro and check. No help. So, called BR 549 Edelbrock for thoughts, and pulled the carb top. I cleaned and blew out the idle adjustment ports after pulling the screws, pulled the boosters, and cleaned and blew out the main jet passages, then the boosters themselves, including the small idle jet passages. And, after this, although losing confidence, it again runs like a scalded dog. At first blush the power and responsiveness are better.....but need road testing. The problem must have been that some small bit got into one of the boosters after I changed the jets. I had tried to clean the bowl area before the change, but this is what happened. And, a friend who is driving the heck out of his rusted out 63 427 galaxy, says, you need a filter. I have had a filter, one of the clear plastic ones, on since the beginning, but there was some crap almost like mud in the bowls......so, if a problem like this arises for yoose, you can try cleaning those boosters and passages.
Back in the later 1960s, as our '66 Newport progressed more into be a "used car", the OEM fuel filter Chrysler used was the silver metal one. I had discovered the opaque Fram filter where the fuel level could be seen through the plastic, and felt that might be a better one to use, so we did.
Then every time the hood was up and the engine running, it was easy to see "how things were going". Rather than a consistent level of fuel in the filter, it would vary. Especially in the hot summer months! Sometimes, it would be 1/4 full, other times more like 1/2 full (which was more where it seemed to like to be), as other times it would appear empty. All the while, the engine ran like it did not care how much fuel was in the filter! Never did have any issues starting or running, even with an "empty" fuel filter! Although to look at it, it should have not been doing what it was doing with an "empty" filter!
I asked the old-line Chrysler service manager at the local dealership about that. His reply was that "you can't go by that". Which meant that Chrysler put the metal filters on the cars for a reason! I kept using the opaque Fram plastic filters for general principles and the car never faltered, even with a fuel filter that APPEARED to be empty. Just another unexplained mystery, it seems, as to how the fuel went through the filter without getting into the outer sections of the filter. Didn't have the capabilities to "cut one open" to see how it worked. FWIW, the fuel filter was mounted by the fuel pump, in the OEM orientation, with the lines being almost vertical rather than laying flat near the valve cover area.
It kind of sounds like the "brown" gas you are getting might be indicative of "rust" in the lines? Or some sort of algae situation in the fuel tank?
Just some thoughts, experiences, and observations.
CBODY67
Then every time the hood was up and the engine running, it was easy to see "how things were going". Rather than a consistent level of fuel in the filter, it would vary. Especially in the hot summer months! Sometimes, it would be 1/4 full, other times more like 1/2 full (which was more where it seemed to like to be), as other times it would appear empty. All the while, the engine ran like it did not care how much fuel was in the filter! Never did have any issues starting or running, even with an "empty" fuel filter! Although to look at it, it should have not been doing what it was doing with an "empty" filter!
I asked the old-line Chrysler service manager at the local dealership about that. His reply was that "you can't go by that". Which meant that Chrysler put the metal filters on the cars for a reason! I kept using the opaque Fram plastic filters for general principles and the car never faltered, even with a fuel filter that APPEARED to be empty. Just another unexplained mystery, it seems, as to how the fuel went through the filter without getting into the outer sections of the filter. Didn't have the capabilities to "cut one open" to see how it worked. FWIW, the fuel filter was mounted by the fuel pump, in the OEM orientation, with the lines being almost vertical rather than laying flat near the valve cover area.
It kind of sounds like the "brown" gas you are getting might be indicative of "rust" in the lines? Or some sort of algae situation in the fuel tank?
Just some thoughts, experiences, and observations.
CBODY67
Very good points. I have never figured how the filter can have so much air volume. With any air, I would think it would be pushed and vented until enough liquid lifts the float. But no. You said it, a mystery. One of the very sad things that happened last year, after I cleaned and coated the tank. I was pouring fuel from my closed race can and found some dark color, so stopped. How, how, how did this crap get into my nice clean fuel can, I do not know. But, I dumped some of it into my nice clean tank, and may suffer for some time. Fortunately, I do not see it in the filter. Before the tank deal, the filter would load up with some kind of green stuff, almost like paint or dye. The OEM AFB was full of it. A continuous battle. I just go back to my early days.....I drove the wheels off these things, and rarely had a shutdown. Mostly, points issues along the road a few times. But, they just ran.
Was all of the fuel in the closed can darker or just the lower sections of fuel, with the fuel near the top being normal? How long had it been in there and was it E10-type fuel or ethanol-free?
Just curious,
CBODY67
Just curious,
CBODY67
No, I use several race jugs for ethanol free gas, then add sea foam for this car, since I have not gotten to the point of long drives. Not sure of an answer to how much got into the tank.....just realized it was dirty, and stopped, with a lot of black crap in the bottom....no idea where it came from. I had two jugs, I think filled at same time, one clean. And I am fanatic about clean fuel cans.....so no idea how this happened.
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