#61  
Old 01-18-2023, 10:49 AM
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Originally Posted by Rob in NH View Post
Wow, never knew how this carb would get all the carb guru's upset, Cliff, have a cup of coffee and relax LOL.
Rob - as I posted in my last post; if you are happy, then that is what matters.

As to being upset; I didn't see any posts that were upset with you.

Many of us have been professionally working on carburetors for decades (I built my first Holley in 1959). Over the years, we learn that virtually ALL carburetors have a "best" in one or more categories. (And if there is a "best", then there certainly must be a "worst").

When a question such as you posed is asked, we attempt to give the original poster the benefit of experience.

The internet is full of conflicting opinions, and that is fine. One just has to determine which opinion is correct.

Many of the folks here (Cliff for certain, I don't know about Kenth) are retired, and as Cliff stated "have no ax in the ax fight (or maybe it was "dog in the hunt), same cliche". I should have retired two decades ago, but having difficulty finding a buyer for the business (looks like son will take over part of it).

The point being, we are basically offering free advice. What is done with that advice is up to each individual.

When selecting a carburetor; one should look at several categories, depending on one's eventual use:

(1) Initial cost (the ONLY category in which the e imitation is "best")
(2) Service cost
(3) Performance (HP)
(4) Performance (driveability)
(5) Fuel economy
(6) Reliability

(Professional opinion) the e imitation will finish dead last against virtually all other entrants in categories 2~6.

I know you have posted you are currently happy, after all, the car is running; but since you now have time, I would highly suggest looking for a rebuildable Q-Jet and a manifold to accept it when you frequent swap meets.

Jon

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  #62  
Old 01-18-2023, 11:17 AM
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Interesting stuff. Seems like I recall the annular boosters on the AV2 loose about 50 cfm against the regular boosters like a AFB. At some point of performance you will notice that, but that will never show up on a stock 350. IRC, some guys pull the boosters on the AVS2 and put regular booster in them? The AVS2 is popular for the 68 to 71 Mopar’s that ran the original AVS. I have a tunnel ram combo I am working on I was thinking about using an original Carter AVS carb, probably not a AVS2.


Our experience has been you can take about any aftermarket 600 cfm carb to replace a 2 bbl and you will be blown away by the power increase and probably run just fine, improvement over and old used 2 bbl in pretty much every direction. It is only after a year or two and run some fuel thru the new carbs and all the poorly mfg’s parts inside the carb comes unraveled you realized what the expert carb guys where taking about.

But you do not always get that lucky. We have a nearly new Holley 750 Ultra that we bought cheap because it wouldn’t it run right on a friend’s 383 SBC 430HP engine. Speedway motors shop in Lincoln,NE worked on it, even had it on the dyno, eventually said it was “too big”. The guy just thru money at stuff and hires projects out. So he switched to a smaller Holley street avenger, it didn’t run right. Then he put a FI tech system on it. That didn’t work for him either. LOL…He ended up with a qjet on it! Another friend bought the basically new $800 Holley 750 ultra for $200. His q jet on his 455 was running terribly rich. So we helped him try the Holley. Basically new yet, it ran like total crap. Took it apart and had huge jets in it like it was an 850, jetted into the 80s.. Appeared the previous tuner was trying to mask a problem it had. We spend a good part of the day messing with the ultra and never could get it to run very well, seemed like it was missing 50 HP. Out of desperation we took the top off the qjet and Jet’s upgrade, the adjustment screw holding the primary metering rods had cam undone. Tightened that up, and pulled the ultra off and put the jet qjet back on, it felt like we gained 50 HP. Still have no idea what is wrong with the 750 Ultra. I was able to tune it so it at least runs well cruising. Full throttle though that new carb still has something very wrong.


Last edited by Jay S; 01-18-2023 at 11:36 AM.
  #63  
Old 01-18-2023, 11:21 AM
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Thanks for the advice Jon.


Last edited by Rob in NH; 01-18-2023 at 12:17 PM.
  #64  
Old 01-18-2023, 01:34 PM
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Originally Posted by Rob in NH View Post
I installed a edelbrock intake and a 600 performer carb, it runs good and seams to have woke up the engine.
Hi Rob, a very thoughtful Christmas gift from your kids,
Enjoy it and if you need help doing any tuning glad to help, I'm just a town over.

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  #65  
Old 01-18-2023, 02:19 PM
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Originally Posted by Formulajones View Post
Wasn't meant towards you specifically, it's just what I see in general from my own personal experience.

For what you're doing those smaller eddy carbs generally work ok on stock type engines so you'll probably be just fine. It's just the general consensus of those carbs overall isn't that great.
I helped a guy wedge in a 350 Corvette motor into a 1952 Henry J several years ago. He had a dual quad set up with these cheap carbs. I asked him about the carbs, and he told me there were readily available and cheap. He thought they would work well. They do work but that is it. I think he never really got the car finished and on the road after all the years of modifications and fabrications he performed. Sad too, he got older and lost interest, so he let the car sit. I've no idea if he still has the car.

  #66  
Old 01-18-2023, 03:06 PM
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Originally Posted by shaker455 View Post
Hi Rob, a very thoughtful Christmas gift from your kids,
Enjoy it and if you need help doing any tuning glad to help, I'm just a town over.
Thanks Jeff, I will keep that in mind.

  #67  
Old 01-18-2023, 04:56 PM
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"Many of the folks here (Cliff for certain, I don't know about Kenth) are retired, and as Cliff stated "have no ax in the ax fight (or maybe it was "dog in the hunt), same cliche". I should have retired two decades ago, but having difficulty finding a buyer for the business (looks like son will take over part of it)."

Jon, here in these parts it's "no ax to grind and no dog in the fight", but still pretty much the same thing......

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  #68  
Old 01-18-2023, 05:54 PM
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I have motors with just about all of the choices out there . Qjets, Holleys AND dual Edelbrock clones on my 470' 409. Can't say to Cliff's long term issues but 25 dyno pulls tweaking rods/jets as well as lash and timing I think they did OK

they were not OK out of the box. float levels not even to Edelbrocks specs. A step leaner jets also.
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  #69  
Old 01-18-2023, 05:57 PM
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Originally Posted by carbking View Post
Link CLEARLY shows a SQUAREBORE!

Interesting that e calls it an 800.

Carter called the same configuration a 625. New math???

Jon
Square bore is defined as 4 equal size venturies whose outline forms a square, not the centerlines of the 4 venturi. The flange is dual pattern for squarebore and spreadbore mounting.

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  #70  
Old 01-18-2023, 07:35 PM
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When the secondary butterflies exceed past the axis between the front to rear mounting bolts, it can be considered a spread bore. Anything with all the butterflies within that axis is a square bore. Lots of early carbs had larger secondary bores, but were by no means a spread bore.

The Q Jet was the first carb I ever saw in 1967 that exceeded those boundaries of the axis of front to rear mounting bolts. the Thermo Quad was also of that same design. Holley had to make their interpretation of a spread bore too.

AFBs and AVSs were never considered a spread bore carb in any book, or with any of the people I ever knew in the car business, or hobby.


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  #71  
Old 02-01-2023, 09:26 PM
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Could someone post a picture of how they plumbed the fuel line for an edelbrock?

  #72  
Old 02-01-2023, 10:18 PM
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Quote:
Originally Posted by Jay S View Post
Interesting stuff. Seems like I recall the annular boosters on the AV2 loose about 50 cfm against the regular boosters like a AFB.
Lots of bad info out there.

Each Annular Booster loses 5 cfm so a 20 cfm loss. PERIOD.

Tom V.

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  #73  
Old 02-02-2023, 12:19 AM
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Thanks Tom. There are only annular booster on the primaries, so at most 10 cfm, and they do not look very restrictive to me. I think the annular boosters were a pretty decent improvement.

On the fuel line routing you can move the inlet to the from the right side to to the left side on the carb and run a factory line for a 389 and an AFB. Not an exact fit but much better than routing the line to the back corner of the carb.
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Last edited by Jay S; 02-02-2023 at 12:56 AM.
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  #74  
Old 02-02-2023, 08:40 AM
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again I will probably get flamed for this but the Quick Fuel brawler has been great for me and easy to setup

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  #75  
Old 03-17-2024, 01:35 PM
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Quote:
Originally Posted by Rob in NH View Post
I installed a edelbrock intake and a 600 performer carb, it runs good and seams to have woke up the engine.
Rob, could you give an update on your performer 600? Some gifted me a Qjet, but it’s from national carb, runs but not right. I was looking at that the performer , a street demon 625 and brawler.

  #76  
Old 03-17-2024, 04:44 PM
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It runs really good, no problems with cold or hot startup. I did have one hiccup and that was one of the floats stuck open . It was set wrong from the factory, Shaker 455 came over and set it all up for me , he really knows about everything to do with carburetors of all kinds, highly recommend him for this work.

  #77  
Old 03-19-2024, 11:29 AM
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Originally Posted by Rob in NH View Post
It runs really good, no problems with cold or hot startup. I did have one hiccup and that was one of the floats stuck open . It was set wrong from the factory, Shaker 455 came over and set it all up for me , he really knows about everything to do with carburetors of all kinds, highly recommend him for this work.
Thanks for the update. What model #did you go with?

  #78  
Old 03-19-2024, 01:07 PM
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1406

  #79  
Old 03-19-2024, 11:48 PM
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If you don't want to build a Q-jet, and you're not running a spreadbore only intake, a 750cfm vacuum secondary 4150 is likely the way to go. Set some proform metering blocks up like a classic holley, install the quick change secondary spring kit and go to town.

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  #80  
Old 03-20-2024, 06:45 AM
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"I should have retired two decades ago, but having difficulty finding a buyer for the business (looks like son will take over part of it)."

Same problem here. Have had a couple of "tire kickers" take a look at the business but never got close to a sale. The last one just kept asking questions and taking up WAY too much of my time. It appeared to me that they were just looking for information to start a business on their own without buying mine....good luck with all that.

I decided to close down the rebuilding/restoration portion and just sell parts. Was hoping that was going to be a part time gig, but it's worked it's way into full time and growing bigger by the day. I'm also turning down at least 10 jobs a week, sometimies double that number, so there is still PLENTY of work out there despite it being 2024 and quite a few more options for carburetion/fuel delivery have been added to the market.

I'll add here (keeping in mind I have no dog in the fight) that hardly a day goes by I don't get a call from someone who went down the fuel injection (electric carburetor) path and absolutely HATE them. The Sniper seems to get the most complaints, seldom here too much about the others, but it's ALWAYS the same thing. The love it at first, and after multiple issues and failures occur they want to amputate the entire system and go back to a carburetor.

Personally, IF I were to ever look at any sort of "upgrade" from a carburetor it's going to have 8 bungs in a single plane intake with 8 injectors spraying toward the intake valves, not a "wet flow" TB type set-up, especially with a cold intake manifold. The factory couldn't even get that deal figured out and ditched all those systems by the mid-1990's, and for good reason. With a dry flow intake and individual injectors it's just going to be a LOT better everyplace for the end user.....IMHO.......

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