A knucklehead needs carb advice

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jt.db

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Jun 28, 2018
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Texas
My Car
1973 Coupe- oddball mystery hand me down thats full of surprises
Alright, so I'm finishing up the back end of my mustang, got all the rear wiring done, dome light works, everything works except for the cig lighter and the 2nd click on the windshield wipers. 

I'm 17, and know only about body work.

What is the best thing to do if I'm replacing the carb?

as of right now i have the motorcraft2v, and im missing a lot of vacuum lines, and my emmisions thing was deleted too (1973 car)

Does any of yall also have the original, but completed? I'm looking to replace mine but also convert it to a 4v around the same size, i just do not know what cfm the original is.

If i replace mine with a 4v carb do i have to change the intake as well?

and where would i find the vacuum diagram for the car as well?

My lines are colorless as they have faded, the engine bay on this car was neglected, as with the rear of the car as well.

and the middle.

the car does not run right, and i have no idea how to tune it, check/adjust timing either.

it starts cold idling low, then idles higher onces it warms up, but theres a phase inbetween where it cant run itself and will die, where you have to turn it over.

Ive replaced the trunk floor, gas tank, filler neck, sending unit (i put a new filter on) replaced the rubber on the gas lines, cleaned out the metal parts, with a new filter going to the carb as well. so i know its not a fueling issue.

i have yet to check the distributor, spark plugs, & spark plug wires.

 
By "emissions thing", I assume you mean the EGR valve and plate under the carb? Post a couple good pics of your current setup. I have attached a PDF witha bunch of the vacuum diagrams from the '73 shop manual. 

The Motorcraft 2100 carb is a very good design and the one used on the 302 was 350cfm IIRC.  If it starts and idles low when cold, then your choke is most likely either inoperative, or out of adjustment. They are incredibly simple units and a great one to learn how to rebuild and adjust. Rebuild kits cost under $20 and will probably take you a couple hours your first time. 

Personally, since the car does run, I would recommend, if you haven't already, purchase the 73 shop manual set from a Mustang vendor. You can learn to do the basics and see real results.

If you are going to swap to a 4 barrel, then you'd want a carb in the 500 or 600 cfm range. You'll definitely need to swap intakes,, the go to Edelbrock Performer 2121 is $230 from Summit. Their Summit branded carb is another excellent unit, I'd recommend the 500cfm here.

https://www.summitracing.com/parts/sum-m08500vs/overview/

1973_ServiceManual_Vol6_EngineEmissions_Mustang.pdf

 

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By "emissions thing", I assume you mean the EGR valve and plate under the carb? Post a couple good pics of your current setup. I have attached a PDF witha bunch of the vacuum diagrams from the '73 shop manual. 

The Motorcraft 2100 carb is a very good design and the one used on the 302 was 350cfm IIRC.  If it starts and idles low when cold, then your choke is most likely either inoperative, or out of adjustment. They are incredibly simple units and a great one to learn how to rebuild and adjust. Rebuild kits cost under $20 and will probably take you a couple hours your first time. 

Personally, since the car does run, I would recommend, if you haven't already, purchase the 73 shop manual set from a Mustang vendor. You can learn to do the basics and see real results.

If you are going to swap to a 4 barrel, then you'd want a carb in the 500 or 600 cfm range. You'll definitely need to swap intakes,, the go to Edelbrock Performer 2121 is $230 from Summit. Their Summit branded carb is another excellent unit, I'd recommend the 500cfm here.

https://www.summitracing.com/parts/sum-m08500vs/overview/
From what i saw the 2121 looks like its for the 289/302, the 2665 would be for the 351 4v right? and I'll be sure to send pictures of the area, i just have not done it just yet. and is it easier to delete the egr valve or buy the intake that isnt marked "Non EGR"

 
2V and 4V actually refers to the head design, the 4V heads (which were used with 4-barrel carburetors) have much bigger intake and exhaust ports. To put a 4-barrel carburetor on you will want a 4-barrel manifold for a 2V engine. Even though a 4V manifold will bolt up to a 2V head the mismatch in port size is very inefficient. 2V exhaust manifolds will leak on 4V heads.

You can see the differences here:

https://www.7173mustangs.com/thread-351c-2v-4v-manifold-gasket-comparison?pid=251662#pid251662

And here, intake sides, with 2V head on top and 4V on bottom



 
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2V and 4V actually refers to the head design, the 4V heads (which were used with 4-barrel carburetors) have much bigger intake and exhaust ports. To put a 4-barrel carburetor on you will want a 4-barrel manifold for a 2V engine. Even though a 4V manifold will bolt up to a 2V head the mismatch in port size is very inefficient. 2V exhaust manifolds will leak on 4V heads.

You can see the differences here:

https://www.7173mustangs.com/thread-351c-2v-4v-manifold-gasket-comparison?pid=251662#pid251662

And here, intake sides, with 2V head on top and 4V on bottom

and im assuming that there is no way to mount the 4 barrel carb properly, without changing the heads, as well as the intake right

 
No, you do not need to change the cylinder heads to change from a two barrel carb to a four barrel carb- just the intake manifold. The carburetor flange on the intake needs to match the carburetor you are using.

I think you have a Windsor small block (not a Cleveland) so the intake manifold situation is pretty straight forward to get one that will accept a four barrel carb...

 
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No, you do not need to change the cylinder heads to change from a two barrel carb to a four barrel carb- just the intake manifold. The carburetor flange on the intake needs to match the carburetor you are using, and you can buy an intake manifold that has a four barrel carburetor mounting flange but has ports to fit the 2V heads.
aaah okay, so This intake would work to use the 4b carb on the 2v head for now, until i can fully convert it

 
Yes, that one will work just fine. However, I agree with Hemikiller, I would get it running correctly with the two barrel carburetor firdt. Be good experience rebuilding it, and after you get it running you'll be able to see if the engine needs anything else. You don't want to install the 4-barrel manifold and the find out the engine needs rebuilt or a valve job.

You can get vacuum hose diagrams here. However, if all of the emissions have been removed and you don't need to replace them to get it registered I would keep it as simple as possible. A single vacuum advance and the one vacuum hose connecting it to the carburetor.

https://www.7173mustangs.com/thread-vacuum-hose-diagrams?pid=246021#pid246021

 
No, you do not need to change the cylinder heads to change from a two barrel carb to a four barrel carb- just the intake manifold. The carburetor flange on the intake needs to match the carburetor you are using.

I think you have a Windsor small block (not a Cleveland) so the intake manifold situation is pretty straight forward to get one that will accept a four barrel carb...
it is a cleveland as the rad hose comes out vertically, one of the differences between the windsor and cleveland

 
Yes, that one will work just fine. However, I agree with Hemikiller, I would get it running correctly with the two barrel carburetor firdt. Be good experience rebuilding it, and after you get it running you'll be able to see if the engine needs anything else. You don't want to install the 4-barrel manifold and the find out the engine needs rebuilt or a valve job.

You can get vacuum hose diagrams here. However, if all of the emissions have been removed and you don't need to replace them to get it registered I would keep it as simple as possible. A single vacuum advance and the one vacuum hose connecting it to the carburetor.

https://www.7173mustangs.com/thread-vacuum-hose-diagrams?pid=246021#pid246021
Alright, so i adjusted the knob. it was all the way to the rich side i think, it was to the left. moved it over a little bit. now the car idles better and shifts better. Crazy how such a small adjustment changed the whole cars feeling.

 
If the engine is a 73, it looks like someone did eliminate the PCV valve and replaced it with a spacer from an earlier car with the vacuum port. Glad you got it running better. Not sure how I thought it was a 302 car. What was the "knob" you turned?

Intake for the 2V 351C

https://www.summitracing.com/parts/edl-2665/overview/make/ford

You'll hear a lot of differing opinions on what size carb to use for the 4 barrel swap. Here's mine - if you plan on keeping the engine stock and never doing anything other than a stock rebuild and the mildest of cams and a dual exhaust with manifolds - get a 600 cfm. If you plan on headers, a larger cam etc - get a 750. Again, the Summit carbs are a great value and run really well - I have the earlier Holley 4010 model on my '71 and am very happy with it.

 
If the engine is a 73, it looks like someone did eliminate the PCV valve and replaced it with a spacer from an earlier car with the vacuum port. Glad you got it running better. Not sure how I thought it was a 302 car. What was the "knob" you turned?

Intake for the 2V 351C

https://www.summitracing.com/parts/edl-2665/overview/make/ford

You'll hear a lot of differing opinions on what size carb to use for the 4 barrel swap.  Here's mine - if you plan on keeping the engine stock and never doing anything other than a stock rebuild and the mildest of cams and a dual exhaust with manifolds - get a 600 cfm. If you plan on headers, a larger cam etc - get a 750. Again, the Summit carbs are a great value and run really well - I have the earlier Holley 4010 model on my '71 and am very happy with it.
I'm planning to make 330 hp max as i dont need anything over that at 17, so just an intake swap, maybe engine/trans rebuild to service it, only modifications would be a carb and intake. (and new exaust)

its the side thing on the passenger side where it has the 2 arrows and 7 slots saying lean clockwise. it was full rich, turned it to the middle and the car idled better, shifted better too. i just got my paycheck today so i bought the rear window weatherstrip and the rope for it as well. ill let yall know if i shatter my rear window.



after moving the dot to the middle (i made sure to take before pictures in case i messed up) it was acting a-lot better. shifts much more smoothly as it doesnt idle high then low then high, it used to jolt into gear between R and D but it is now seamless almost. Park and Reverse have a very small shake, putting it into reverse from park will make it idle low for a few seconds then it will shoot back up (HEAT ON, ALL LIGHTS INCLUDING DOME, While applying brakes) so it can handle being under load without stalling out now as well. kicking on the ac wont shut the car off as well.

But please do inform me on how to delete the EGR  thing as it has empty lines that dont go anywhere, and makes the car seem less tidy. 

When i have the new plugs, wires, & distributor caps im going to re-route it nicely. as of right now its a pigeon nest in there.

 
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If the engine is a 73, it looks like someone did eliminate the PCV valve and replaced it with a spacer from an earlier car with the vacuum port. Glad you got it running better. Not sure how I thought it was a 302 car. What was the "knob" you turned?

Intake for the 2V 351C

https://www.summitracing.com/parts/edl-2665/overview/make/ford

You'll hear a lot of differing opinions on what size carb to use for the 4 barrel swap.  Here's mine - if you plan on keeping the engine stock and never doing anything other than a stock rebuild and the mildest of cams and a dual exhaust with manifolds - get a 600 cfm. If you plan on headers, a larger cam etc - get a 750. Again, the Summit carbs are a great value and run really well - I have the earlier Holley 4010 model on my '71 and am very happy with it.
But yessir i did confirm its a Cleveland motor on the yellow sticker on the cowl, and the way the radiator hose goes into the motor (motor is the one that came with the car too)

 
Update on the mustang: No trim, No window again. i put the window in once already but its back out again for the headliner. I managed to finally get my hands on the emblem for the side of the roof, itll be here in 3 days.

i have the first section of the headliner glued in, its proving extremely difficult, luckily I managed to convince my parents to let me borrow the garage for the "weekend" which has now turned in to a week.

Wiring harness has been fully repaired and wrapped in the back (Tail Light Section) working to the front of the car... soon

The weather is warming up again, and the car no longer stays running by itself

Before i order the new intake and carb I wanted to confirm deleting the EGR is a bolt on affair where if you buy a non EGR intake i can get rid of that god awful thing in between the carb and Intake.

 
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