Carb Swap?

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GTX63

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Ty
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I had never seen a spread bore on a stock GM that's why I asked. If vehicle runs good with it that's great but I wouldn't toss the original Q jet away.

As a young kid in 1984, I bought a 1965 Chevy Caprice off the original owners. They had seen the car inside a Chevrolet dealership showroom and wanted it. The salesman said it was a display only and the first one they received with a 396 (replacing the 409). They said sell it or no sale, so the dealership did the deal.
Anyway, it was a factory 325HP 396, with a GM stamped Holley carb, oval port heads but a solid lifter cam. In other words, GM hadn't sorted out the specs completely yet, or had all the correct parts available, and mixed it with high end components. I don't recall now, but I had traced the numbers and codes and the engine was one of the first 100 produced and literally weeks after the introduction. The motor was tired, sucked gas and needed more work than I was capable of, but it was a fun car and of course, worth a lot more now than I can imagine.
 

fast 99

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As a young kid in 1984, I bought a 1965 Chevy Caprice off the original owners. They had seen the car inside a Chevrolet dealership showroom and wanted it. The salesman said it was a display only and the first one they received with a 396 (replacing the 409). They said sell it or no sale, so the dealership did the deal.
Anyway, it was a factory 325HP 396, with a GM stamped Holley carb, oval port heads but a solid lifter cam. In other words, GM hadn't sorted out the specs completely yet, or had all the correct parts available, and mixed it with high end components. I don't recall now, but I had traced the numbers and codes and the engine was one of the first 100 produced and literally weeks after the introduction. The motor was tired, sucked gas and needed more work than I was capable of, but it was a fun car and of course, worth a lot more now than I can imagine.
Scrapped 100's and 100's of vehicles from the mid 70's until early 2000's. If I could remember what they were probably cry for a week. Give you an example of one I remember because sold it to a friend. Was a 65 Chevelle convert about 1976 or 77 $250.

Anyway, back the Holley subject. Know GM installed Holley's from the factory. Was referring in particular to the spread bore.
 

SirRobyn0

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305
I paid a little over 300 for a stage 2 quadrajet from national carburetors in Florida. Stage 2 is fir a motor with cam, intake and hedders. They tune it for you so it's ready to go right out the box. That guy will save you about 100 bucks to rebuild it. Score!
National is good stuff. There are no carb shops left in my area, I'm good at doing them and know the Q-jet pretty well but if a carb has bad throttle plate bushings, I have no way to fix that, so that is when we call National Carburetor. Or sometimes O'Reilly's as O'Reilly's is a distributor for National and can sometimes get it to us a little faster. But I always prefer doing business with National directly as I know the carb hasn't been sitting on a shelf upside down for decade, which could happen at O'reilly's.
 

Matt69olds

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455 Olds
The Qjet was the factory go to 4 barrel on GMs for 20+ years for a reason. Believe it or not, brand new they used to start with little more than a turn of the key and a single pump on the pedal. I buy my rebuild kits from Quadrajetpower.com.
Edelbrocks are popular replacements because they are ready to go out of the box, and well, easier to find that a new Quadrajet. That said, I currently have two in use and they are, to me, a C- substitute.
Qjets are not hard to tune unless the engine has issues or you are trying to do it flying by the seat of your pants.
Understanding the mixture screw adjustments, setting the idle, using the lean drop method, etc are not hard concepts if you learn the steps and procedures correctly from the start.
Try closer to 40 years!!

The “good” Q-Jets started in the early 70s, and production ending in 1990.
 

Matt69olds

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The Qjet was the factory go to 4 barrel on GMs for 20+ years for a reason. Believe it or not, brand new they used to start with little more than a turn of the key and a single pump on the pedal. I buy my rebuild kits from Quadrajetpower.com.
Edelbrocks are popular replacements because they are ready to go out of the box, and well, easier to find that a new Quadrajet. That said, I currently have two in use and they are, to me, a C- substitute.
Qjets are not hard to tune unless the engine has issues or you are trying to do it flying by the seat of your pants.
Understanding the mixture screw adjustments, setting the idle, using the lean drop method, etc are not hard concepts if you learn the steps and procedures correctly from the start.
Besides people not understanding how they operate, unfortunately you can’t fix decades of wear and tear with a cheap autozone rebuild kit and a can of carb cleaner.

The engine will never run right if the throttle shaft bores are worn out. People never remove the air bleeds to clean out the gunk inside. Then try to bolt a carb from one family onto something completely different and then wonder why it runs like crap.
 

saig55

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K10 Silverado
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305
I don’t have the expertise… that is why I don’t mind farming some stuff out. This man has been a mechanic for over 50 years… these old smart guys are slowly fading away..
 

Ricko1966

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c20
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I don’t have the expertise… that is why I don’t mind farming some stuff out. This man has been a mechanic for over 50 years… these old smart guys are slowly fading away..
Yes, we determined yesterday that @bucket was the last one!!!!
 

82sbshortbed

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National is good stuff. There are no carb shops left in my area, I'm good at doing them and know the Q-jet pretty well but if a carb has bad throttle plate bushings, I have no way to fix that, so that is when we call National Carburetor. Or sometimes O'Reilly's as O'Reilly's is a distributor for National and can sometimes get it to us a little faster. But I always prefer doing business with National directly as I know the carb hasn't been sitting on a shelf upside down for decade, which could happen at O'reilly's.
Yeah they're great! I called them when looking for a quadrajet. He was very helpful and asked what I was planning to do to the engine. I told him a cam, intake and hedders. That's when he recommended that one and I've been really happy with it. I was thinking about getting another one for the 84 to replace the edelbrock on there. If I do ill get it from them.
 

Finkaire

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California
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Loren
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1984
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Silverado c10
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305
Quad gone through, happy happy happy
 

mtbadbob

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V20
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350
Try closer to 40 years!!

The “good” Q-Jets started in the early 70s, and production ending in 1990.
The W-30 7040256 & 258'S are like gold bars these days!
 

potent rodent

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indiana
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butch
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1500
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i like the quadrajet good fuel milage , also the holley spread bore good milage till u put your foot into it
 

saig55

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K10 Silverado
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305
Got it back and he said it had never been apart. Looked new on the inside..
Weekend project…
Does anybody have a picture or something to show me how all the linkage hooks up.. I believe my transmission linkage is not hooked up right now
 

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