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Discussion Starter #1
I have a 74 w 350.

I just did new headers, plugs and wires.

The car runs like ****. Sluggish on take off, and surging while I am trying to cruise. It started running like this before I even did the headers and plugs.

I just had new exhaust installed with Flowmaster 40's and turn downs before the rearend.

I have been trying to figure all this out on my own because I really want to know how to work on my own car but I am getting frustrated. Its one thing to swap out parts, its another thing to know how to tune and dial it in so it runs right and you dont look like a dip**** at the local cruise spot.

So from what I have read everything points to the carb. So I got carb cleaner sprayed the **** out of it. Still runs like ***. It runs better with the air filter off..but not much.

So are there adjustments I can make to the carb? Should I rebuild it? or should I just bite the bullet and put on a new manifold and 4 barrel carb? Should I just put a new 2 barrel? Stock 2 barrel is a Rochester correct?

The next step is to bring it to a shop and have them look at it but I really want to figure it out.

Any help appreciate...Maybe someone from my area can suggest a good shop? Or maybe someone could give me a hand? I appreciate any help. :D
 

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So are there adjustments I can make to the carb? Should I rebuild it? or should I just bite the bullet and put on a new manifold and 4 barrel carb? Should I just put a new 2 barrel? Stock 2 barrel is a Rochester correct?

The next step is to bring it to a shop and have them look at it but I really want to figure it out.

Any help appreciate...Maybe someone from my area can suggest a good shop? Or maybe someone could give me a hand? I appreciate any help. :D
Sounds like you got a stuck float and sounds like you need a rebuild and yes you can tune it.

If you're gonna get a replacement go ahead and go for the 4 barrel setup. You will be impressed with the power difference. And if you really dont want to look like a "Dip****" I would recomend picking up a david vizard book or one of the ones from car tech inc they are pretty good and they don't write their books "over your head".
 

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Discussion Starter #3
Sounds like you got a stuck float and sounds like you need a rebuild and yes you can tune it.

If you're gonna get a replacement go ahead and go for the 4 barrel setup. You will be impressed with the power difference. And if you really dont want to look like a "Dip****" I would recomend picking up a david vizard book or one of the ones from car tech inc they are pretty good and they don't write their books "over your head".
Ok so if I do the manifold and carb what combo should I get...

Im going to assume an Edelbrock Performer manifold cuz it appears thats what everyone uses. But what about a carb...Edelbrocks look easy to tune, but I know people say Holley is the way to go....

I will definitely look into those books, I dont have a big Nova support group in my area so other than SNS Im on my own.

Thanks
 

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id say go with the performer if its a stock motors If you've some bolt ons and such go with the rpm. As for the carb, edelbrocks are real good if you wanna just get it on there set it once and be done with it. But if your really into tuning it and messing with it alot go with a holley. For example on my nova I would never run an edelbrock due to its mainly a race car and holleys are so much easier to tune. But on my k5 blazer I like the edelbrock cause it starts up every day no problems.
 

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On the edelbrock carbs you can get a vaccum pressure test guage and you just turn the knobs until you get them to a certain vaccum and it will run like a champ holleys are a little different. I like edelbrock cause they are a little more user friendly for the guys like me that dont like retuning carbs all the time. If you want I'll find out that vaccum pressure that is has to be set at I can't remember its been some years now.
Ok so if I do the manifold and carb what combo should I get...

Im going to assume an Edelbrock Performer manifold cuz it appears thats what everyone uses. But what about a carb...Edelbrocks look easy to tune, but I know people say Holley is the way to go....

I will definitely look into those books, I dont have a big Nova support group in my area so other than SNS Im on my own.

Thanks
 

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Gee, I wonder why I never have to "re-tune" my Holley's or Demon's? I just don't understand where this comes from. If a Holley is setup and running correctly today, there is nothing that would cause it to run differently a year from now, other than dirt and fuel deposits--which will affect an Edelbrock or Weber or Zenith or Mikuni or any other carb.
As to the original post, I'd figure out what went wrong BEFORE you decide to change the carb; you may find it's something else. Then, a Performer and a Q-Jet would be the best combo for a daily driver.
 

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Discussion Starter #7
On the edelbrock carbs you can get a vaccum pressure test guage and you just turn the knobs until you get them to a certain vaccum and it will run like a champ holleys are a little different. I like edelbrock cause they are a little more user friendly for the guys like me that dont like retuning carbs all the time. If you want I'll find out that vaccum pressure that is has to be set at I can't remember its been some years now.
That would be great...thanks
 

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Discussion Starter #8
Gee, I wonder why I never have to "re-tune" my Holley's or Demon's? I just don't understand where this comes from. If a Holley is setup and running correctly today, there is nothing that would cause it to run differently a year from now, other than dirt and fuel deposits--which will affect an Edelbrock or Weber or Zenith or Mikuni or any other carb.
As to the original post, I'd figure out what went wrong BEFORE you decide to change the carb; you may find it's something else. Then, a Performer and a Q-Jet would be the best combo for a daily driver.
Which Q-jet?
 

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Tune up

When your changing wires and spark plugs, you should have changed the fuel filter too. If your gonna do a tune up don't do it halfways, change everything.
Maybe it's your fuel pump not getting enough fuel pressure. Does it idle fine?
 

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Discussion Starter #10
When your changing wires and spark plugs, you should have changed the fuel filter too. If your gonna do a tune up don't do it halfways, change everything.
Maybe it's your fuel pump not getting enough fuel pressure. Does it idle fine?
Yes appears to idle fine but again I am no expert....Sounds choppy but I dont know how much of that is just the way the exhaust is suppose to sound...I can try and do a sound bite of it..
 

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As to the original post, I'd figure out what went wrong BEFORE you decide to change the carb; you may find it's something else. Then, a Performer and a Q-Jet would be the best combo for a daily driver.
Yup, it may not be your carb. Check your vacuum lines, distributor advance and filters. A shope manual will help a lot.
 

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Yup, it may not be your carb. Check your vacuum lines, distributor advance and filters. A shope manual will help a lot.
I second that. The first thing they teach you in carburetor school is that 90% of all diagnosed carburetor problems are not in the carburetor. Points or electronic ignition? Did you replace the distributor cap & rotor button. With the ignition off, if look into the carb and work the throttle, do you see a spray of gasoline? (Should look like a water gun spraying.) You could have a bad accelerator pump. How many miles are on the engine? If you have passed the 100,000 mile mark, the timing chain will be stretched and the camshaft may be missing a lobe. You just installed new plugs, right? Pull the plugs back out. Lay them in the order they came out. Check the color of the plugs. (They should all be the color of chocolate milk. If on doesn't match, that's the location where you start.
 

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They should all be the color of chocolate milk
You using a book from the 60's? When my car is tuned where it runs best, the plugs come out looking just about the same as when they went in. To get to chocolate milk, it takes way too much jet.
 

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You using a book from the 60's? When my car is tuned where it runs best, the plugs come out looking just about the same as when they went in. To get to chocolate milk, it takes way too much jet.
Nope. I'm looking at the spark plugs that came out of my daily driver from last Saturday.
 

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I second that. The first thing they teach you in carburetor school is that 90% of all diagnosed carburetor problems are not in the carburetor. Points or electronic ignition? Did you replace the distributor cap & rotor button. With the ignition off, if look into the carb and work the throttle, do you see a spray of gasoline? (Should look like a water gun spraying.) You could have a bad accelerator pump. How many miles are on the engine? If you have passed the 100,000 mile mark, the timing chain will be stretched and the camshaft may be missing a lobe. You just installed new plugs, right? Pull the plugs back out. Lay them in the order they came out. Check the color of the plugs. (They should all be the color of chocolate milk. If on doesn't match, that's the location where you start.
chocholate milk spark plugs? havent heard that one before
 
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