Page 1 of 12 123411 ... LastLast
Results 1 to 15 of 167

Thread: Qjet vs Holley

  1. #1
    427
    427 is offline
    Senior Member
    Join Date
    Dec 2012
    Location
    Melbourne
    Posts
    408

    Default Qjet vs Holley

    Due to popular demand, here is the biggest thread of the year! I'll open the can of worms. I have a Qjet on my 350 Tonner, with a matching Qjet performer spread bore maifold. If i get 400 flywheel i will be happy. I have thuoght they performed well. Big secondary boot. Shit fuel economy, but you get that.

    Convince me to change to a Holley!
    Last edited by Smitty2; 15-02-2019 at 07:38 AM.

  2. #2
    been here .......too long Smitty2's Avatar
    Join Date
    Mar 2007
    Location
    bayside Melbourne
    Posts
    9,476

    Default

    ... not me

    Holleys? don't understand 'em... but I do Quaddies*
    so I build tune reco my own Quaddies and use them
    on my race car. 220 odd rwkw (in a 1190kg car)
    means it is no slouch

    GM used them on everything ... I mean on EVERYTHING
    from little engines up to their largest (before swapping to EFI)
    people who say they are rubbish forget there are far more
    Quaddies in existence on street cars than any other carb
    plus no hassles with throttle hookups or fuel lines


    *got taught by a couple of gurus in the late 70s, early 80s
    and still have notes/guides from then
    Last edited by Smitty2; 15-02-2019 at 09:00 AM.
    __________________________________
    ONE OF THE Aussie V8 MODERATOR/ADMIN TEAM
    Never late in an AussieV8!
    Club circuit racing...the best fun you can have with your pants on

  3. #3
    Do you ever leave? HQ308Ute's Avatar
    Join Date
    Dec 2011
    Location
    Adelaide
    Posts
    2,572

    Default

    What are Zok's carbs based on?

  4. #4
    Not the Kingswood! hq308's Avatar
    Join Date
    May 2010
    Location
    The Riff
    Posts
    2,156

    Default

    If you have deep pockets and can get someone who knows what they are doing to sort out the quaddy keep it. If your pockets aren't so deep and you want to have a go at tuning it yourself a Holley is a better option IMHO. It's not that quadrajets are bad carbs it's more because Holleys are less complicated and enjoy much more support in the aftermarket. You can buy Holley stuff just about anywhere, the QJ stuff is harder to find.

  5. #5
    casual poster Willie's Avatar
    Join Date
    Jun 2015
    Location
    Bateman Western Australia
    Posts
    244

    Default

    In my experience the quaddie that I have on my 308 now is getting better fuel economy than a 650 Holley it came with.

  6. #6
    Do you ever leave? immortality's Avatar
    Join Date
    May 2010
    Location
    NZ
    Posts
    3,000

    Default

    Quote Originally Posted by Smitty2 View Post
    ... not me

    Holleys? don't understand 'em... but I do Quaddies*
    so I build tune reco my own Quaddies and use them

    *got taught by a couple of gurus in the late 70s, early 80s
    and still have notes/guides from then
    And there is the crux of the issue, I don't think one is better than the other, it's just what you know/use.

    Me, I'm useless with carbs, I have a basic understanding of how they work but no expert in fine tuning, but then I know EFI.

    To me though, the basic Holley carb isn't that fancy, it's what all the other suppliers have added to it over the years that make it what it is today. As someone else mentioned, it's the people like Zok who make speciality bits that make the carb work really well.

  7. #7
    Do you ever leave? EH179's Avatar
    Join Date
    Jan 2008
    Location
    Ipswich. QLD
    Posts
    3,842

    Default

    Quote Originally Posted by 427 View Post

    Convince me to change to a Holley!
    Why? if you're happy with it leave it.
    I would rather sit back and wait until tuning/rebuild time and then see a thread on here, because honestly "who ya gunna call" to fix it?

  8. #8
    427
    427 is offline
    Senior Member
    Join Date
    Dec 2012
    Location
    Melbourne
    Posts
    408

    Default

    I am happy with it. Just trying to stir the pot a little! I actually have a Quick Fuel 950 for my 427. That car is getting the bare bones treatment very soon. I'm not biased, just interested in peoples oppinions. A healthy debate... ☺

  9. #9
    Part of the furniture
    Join Date
    Jan 2017
    Location
    Nth Qld
    Posts
    870

    Default

    Hi
    Run any carb rich and try and tune without airfuel meter your only guessing .
    Run constant rich below 13;1 and u WILL have increased wear and dilute your engine oil a lot . This happens more so on a street car
    Proper tuning
    idle
    part throttle
    accelerating
    cruise
    Power enrichment
    choke
    If u donot set up correctly fuel consumption will be huge . Power / throttle response can suffer as well .

    Quickfuel SS SUPER STREET is the carb to have for adjustability and choke on the street
    The brawler is basically a less adjustable . Donot by the base model
    Now that Holley own them the customer service has turned to shit.
    Just try asking about part throttle cruise its like talking to an Asian phone help --have no idea
    Air bleed tuning is not a black art if u read enough .Theory is general but as with all things 2 cars canbe a little different although principles are the same .
    Last edited by swampy; 15-02-2019 at 08:03 PM.

  10. #10
    casual poster
    Join Date
    Nov 2018
    Location
    Sydney
    Posts
    120

    Default

    Great thread.

    QJs are great carbs, generally well designed, & make great street/strip carbs. The best 4 bbl made was the Carter Thermoquad. It is like a QJ on steroids, production versions were made in 800 & 850 cfm ratings. The 800s were used here on mid 70s Ford 302/351 Falcons. Also used on the 340 Valiant Charger. If you want great reliability, great mileage & plenty of HP, get one from Ebay. The veeeeeery rare Competition Series TQ came in 850 & 1000 cfm versions. I am lucky enough to have two of them....

    Most carbs had design faults/problems that were corrected on later models. The exception is the production series TQ, which was perfect from day one & was not modified to in later models to fix problems....'cause there weren't any.

    The QJ is not so blessed. The early models had leaking fuel wells that drained the fuel bowl; they also used a strange pressure differential fuel inlet valve, which in 1967 was changed to the more common needle & seat arrangement. There are a few other areas where I think the QJ could have been better designed. The screws in the base can come loose & fall into an open intake manifold. Happened to a mate of mine, he was NOT pleased..... The fine thread used in the junk Zinc body casting for the fuel inlet can strip out easily. The two front mounting bolts go through the air horn, to be tightened with a 1/2" spanner; the rest of the air horn screws require a screwdriver. Result: a lot of warped air horns because of unequal bolt tightening. The plastic air valve cam would been better made out of metal, these are known to crack.

    The QJ jets, as well as all Carter 4bbl carbs, have the jets in the carb base, a great design as it keeps the jets covered with fuel; the primary jets are also very close to the boosters for quick throttle response.

    It is a pity more parts like a full selection of metering rods/jets is not available in OZ for the QJ & the TQ. Maybe then we would see more of them of performance cars....

    The Carter AFB/AVS is another carb that was perfect from day one. Was not 'fixed' through the years....as there was nothing to fix! Probably why Edel copied them, although the Edel AVS secondary system is different to the original Carter design. Don't know why, original AVS were great carbs.

  11. #11
    Do you ever leave? immortality's Avatar
    Join Date
    May 2010
    Location
    NZ
    Posts
    3,000

    Default

    Yanks really haven't cared to much about fuel economy so the Holley really was perfect for em

  12. #12
    Do you ever leave? EH179's Avatar
    Join Date
    Jan 2008
    Location
    Ipswich. QLD
    Posts
    3,842

    Default

    Quote Originally Posted by GtoGeoff View Post
    Great thread.

    QJs are great carbs, generally well designed, & make great street/strip carbs. The best 4 bbl made was the Carter Thermoquad. It is like a QJ on steroids, production versions were made in 800 & 850 cfm ratings. The 800s were used here on mid 70s Ford 302/351 Falcons. Also used on the 340 Valiant Charger. If you want great reliability, great mileage & plenty of HP, get one from Ebay. The veeeeeery rare Competition Series TQ came in 850 & 1000 cfm versions. I am lucky enough to have two of them....

    Most carbs had design faults/problems that were corrected on later models. The exception is the production series TQ, which was perfect from day one & was not modified to in later models to fix problems....'cause there weren't any.

    The QJ is not so blessed. The early models had leaking fuel wells that drained the fuel bowl; they also used a strange pressure differential fuel inlet valve, which in 1967 was changed to the more common needle & seat arrangement. There are a few other areas where I think the QJ could have been better designed. The screws in the base can come loose & fall into an open intake manifold. Happened to a mate of mine, he was NOT pleased..... The fine thread used in the junk Zinc body casting for the fuel inlet can strip out easily. The two front mounting bolts go through the air horn, to be tightened with a 1/2" spanner; the rest of the air horn screws require a screwdriver. Result: a lot of warped air horns because of unequal bolt tightening. The plastic air valve cam would been better made out of metal, these are known to crack.

    The QJ jets, as well as all Carter 4bbl carbs, have the jets in the carb base, a great design as it keeps the jets covered with fuel; the primary jets are also very close to the boosters for quick throttle response.

    It is a pity more parts like a full selection of metering rods/jets is not available in OZ for the QJ & the TQ. Maybe then we would see more of them of performance cars....

    The Carter AFB/AVS is another carb that was perfect from day one. Was not 'fixed' through the years....as there was nothing to fix! Probably why Edel copied them, although the Edel AVS secondary system is different to the original Carter design. Don't know why, original AVS were great carbs.
    Well sheeeeit... the guys in Pro Stock missed the memo!

  13. #13
    Senior Member
    Join Date
    Feb 2018
    Location
    Brisbane
    Posts
    635

    Default

    The “modern” Holley. ie XP Series etc. have waaaaayyyy more fuel curve adjustability than any other carb on the market. Other than weber.


    Sent from my iPhone using Tapatalk

  14. #14
    Senior Member
    Join Date
    Feb 2018
    Location
    Brisbane
    Posts
    635

    Default

    If a swap meet 600 vac sec Holley is what you are thinking. Stick with your quaddie.


    Sent from my iPhone using Tapatalk

  15. #15
    Do you ever leave? EH179's Avatar
    Join Date
    Jan 2008
    Location
    Ipswich. QLD
    Posts
    3,842

    Default

    Drugs are bad

Page 1 of 12 123411 ... LastLast

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. A VGC Rochester QJET or 465 Holley for a 253 (QLD)
    By zaczac in forum Wanted (cars & items)
    Replies: 0
    Last Post: 14-12-2011, 09:29 AM
  2. Qjet Overhaul
    By blackhand in forum Holden V8's
    Replies: 14
    Last Post: 09-03-2011, 09:11 PM
  3. Qjet and manifold
    By Unorthodox-racing in forum For Sale Items
    Replies: 15
    Last Post: 22-05-2010, 05:21 PM
  4. Qjet Gasket
    By cunoath in forum Holden V8's
    Replies: 11
    Last Post: 25-08-2008, 09:32 PM
  5. Qjet aussie or u.s.?
    By Q boat in forum Holden V8's
    Replies: 1
    Last Post: 02-04-2008, 09:53 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •