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  1. #51

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    Quote Originally Posted by Walking-Tall View Post
    The primary shafts don't come with the ribbon bushings. If I'm working with a carburetor where there's too much clearance between the primary shaft and the base plate bores, sometimes adding some used (or new, if very loose) bushings tightens up the clearance. There are also channeled areas where they can be positioned if needed.

    The steady idle vacuum you're getting is good, but the mixture screw position discrepancies indicate something is jacked up in the carburetor. The best example I can give of this phenomena is a Holley 650 double pumper recently refurbished, where upon disassembly one mixture screw was found to be very much so turned out further out than the other... and (lack of) quality control and manufacture of newer stuff is why... the image below is of a traditional Holley idle air:fuel discharge hole (controlled upstream by the mixture screw in the metering block) that was never fully drilled through, leaving only an 0.018" passage for idle air:fuel to get through:



    ... where the idle vacuum was pulling idle air:fuel properly through the other, this one had no chance in hell supplying enough, and it's mixture screw was turned out much more than the other... and I guarantee it could not have idled worth a darn from day 1... after that was remedied, the passage hole drilled fully through, everything worked like it should... the mixture screws are equally sensitive and adjusted outward the same amount of turns for best idle.
    Thanks; that will give me something to look for.

  2. #52

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    Quote Originally Posted by darkd0r View Post
    Walking-Tall,
    I have been following your project with great interest and appreciate your efforts very much. However, I don't have any Holley carbs (yet), just Motorcraft 2150's, so no experience and wouldn't know what to ask. So I won't clutter up the thread. I suspect there are many others in the same situation. Thanks for sharing your knowledge. We're out here learning, quietly.
    Glad you are. There isn't too much that's simpler or more reliable than a Ford 2-barrel It's no clutter, thank you for commenting. Quite welcome, and I appreciate hearing from you.
    Mike
    1986 Mustang convertible ---> BUILD THREAD
    Past Fox-chassis "four eyes":
    1983 Mercury Cougar LS
    1986 Ford Thunderbird ELAN
    1980 Capri RS Turbo

    Work in progress website ---> http://carb-rebuilds-plus.boards.net/

  3. #53

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    Quote Originally Posted by JacksAO View Post
    Thanks; that will give me something to look for.
    Good luck with the looking... the reason I began this thread is because so much is hidden (and IMHO, unnecessarily installed within the circuits, and dirt-collecting that's not easily cleaned out, etc.) and anti-tamper with 4180's. I say again, if a 4180 is to remain as it is, as opposed to the way I am dissecting and re-engineering, the cleaning process of the whole primary idle circuit, from the idle feed restrictions behind the primary jets, to the idle mixture screw discharge holes and transfer slots in the base plate, as well as the multitude of passageways and for the FOUR primary idle air bleeds, needs to be repeatedly cleaned and blown out like nobody has ever cleaned and blown out the circuit passages of a carburetor before... as well as all circuit restrictions verified to be consistent side-to-side, in order for it to function somewhere near normally and efficiently.
    Last edited by Walking-Tall; 07-07-2018 at 08:02 PM.
    Mike
    1986 Mustang convertible ---> BUILD THREAD
    Past Fox-chassis "four eyes":
    1983 Mercury Cougar LS
    1986 Ford Thunderbird ELAN
    1980 Capri RS Turbo

    Work in progress website ---> http://carb-rebuilds-plus.boards.net/

  4. #54

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    Important addition for post #49 (largely different primary idle mixture screw adjustments side-to-side):

    "The steady idle vacuum you're getting is good, but the mixture screw position discrepancies indicate something is jacked up in the carburetor."

    In either traditional Holley 2300/4150/4160/etc primary idle circuits and idle air:fuel mixture screw adjustment, or the primary idle circuits and idle air:fuel mixture screw adjustment for 4180's in the base plate, addressing a large discrepancy of idle mixture screws' number of turns out side-to-side is fine for making the engine's idle cooperate, but does not address the primary idle circuit discrepancy (be that incomplete/inconsistent passage/restriction sizing, debris blockage in one side, etc) that will remain for off-idle function, most of the rest of nearly all "normal" low-speed drive-ability and driving, most light part-throttle acceleration prior to the main circuits taking over (sometimes usually, and unnecessarily, all addressed by installing a larger accelerator pump shooter or cam), and even most instances of normal highway cruise speeds are (and should be) easily handled by the primary idle circuits. Hence the need to investigate what is jacked up in such a carburetor... the idle mixture screw adjustment discrepancies are a symptom/clue/hint that something's not right.
    Mike
    1986 Mustang convertible ---> BUILD THREAD
    Past Fox-chassis "four eyes":
    1983 Mercury Cougar LS
    1986 Ford Thunderbird ELAN
    1980 Capri RS Turbo

    Work in progress website ---> http://carb-rebuilds-plus.boards.net/

  5. #55

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    Removed the lead from the jet-side of the primary metering block, where behind I looked for the what and the how of the hidden mystery "emulsion" (booster air correction) bleeds...




    Get a load of these, the brass tubes from within the main wells (shown standing upside-down here). The one tube while still inside showed me a drilled restriction after removing the lead plugs, the other did not, so yes, they had to come out in order to see and measure exactly what is going on in there, and one got destroyed, and that's not going to matter...



    ... so, with clearance around the small diameter of these tubes, giving full main air bleed access to all of these holes... two 0.040" thru-holes (so four of them) are drilled at what lands at about fuel level, and two more 0.029" thru-holes (also four) are drilled at about 5/32" above fuel level. That's over 800% more early-booster-flow-encouraging area connected with the main air bleed at fuel level than is normal in a traditional Holley. The booster-flow-delaying bleeds above those are contradictory and aren't usual in a traditional Holley. Those are connected with an early and rich encouraging 0.044" main air bleed that by it's size later encourages leanness if not dealt with with yet more variables in circuits, feeding annular boosters.


    Some visuals, and the tube shown as it is when inside the main well, to hopefully help explain what's been found...






    Tune in next time where it'll be much easier for me to explain what I'm going to do with pictures of the processes and what the final block circuits will look like with all the hidden unnecessary razzle-dazzle omitted, and it reverted back to basic, simple, reliable, easily clean-able, and efficient function.

    Mike
    1986 Mustang convertible ---> BUILD THREAD
    Past Fox-chassis "four eyes":
    1983 Mercury Cougar LS
    1986 Ford Thunderbird ELAN
    1980 Capri RS Turbo

    Work in progress website ---> http://carb-rebuilds-plus.boards.net/

  6. #56

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    Because, "a picture is worth a thousand words", and will no doubt describe/explain better than a bunch of my wording probably can, here are some sectioned depictions of the 'as is' (was) and 'proposed changes' for booster air correction, eliminating more potentially dirt-collecting or sizing variation variables, and which will later be working with a smaller, more usual size main air bleed, and I suspect smaller than factory main jetting with the annular boosters... to provide a predictable, solid, stable, flat (as opposed to any sluggishness or slope or "curve") WOT air:fuel ratio from the lower speed main circuit activation point (jet + PVCR enrichment) all the way up to maximum engine operating rpm:








    Mike
    1986 Mustang convertible ---> BUILD THREAD
    Past Fox-chassis "four eyes":
    1983 Mercury Cougar LS
    1986 Ford Thunderbird ELAN
    1980 Capri RS Turbo

    Work in progress website ---> http://carb-rebuilds-plus.boards.net/

  7. #57

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    awesome work!
    Jim DeAngelis
    Cornucopia of Useless Knowledge
    Connoisseur of Dearborn Ferrous Oxide
    '83 GT hatch, currently under the knife
    '79 Capri 2.3L n/a, Medium Copper metallic, survivor
    (bought from MRausch82)

  8. #58
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    Fantastically detailed drawings! I'll have some q's at some point about how you've done a few of those...

    My ignorance may be showing with the next question... lol

    Am I understanding correctly that some of these mods in this last post are going to be creating an adjustable emulsion package?
    '85 GT

  9. #59

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    Thanks guys!

    Not ignorance at all, Steve. Yes, completely adjustable IF ever necessary... and a side bonus to these modifications is if ever a restriction gets accidentally dropped down the main well if changing one or whatever, if you remove that main jet, the restriction should be sitting right there looking at you to snatch back outta there, lol. Adjusting of correct "emulsion" (I prefer 'booster air correction', because that's what that aspect, introduced main air bleed air at the fuel level (and often some a bit below that too) in the main well of the main circuit does... corrects the tendency of a booster in a venturi with airflow going thru/past it to be rpm-dependent as to how much it flows, which is most usually increased flow with rpm and increased airflow, but increased disproportionately as to a steady air:fuel ratio. The tendency today of bigger and more "emulsion" and bigger main air bleeds screws up proper booster function real good... starting them sporadic and sluggish and early and rich, and lotsa times being so much introduced air that there isn't a main jet big enough made to get rid of top end lean out, due directly to too much introduced bleed air and too large of main air bleed. Booster behavior should provide at nice flat moderate hard throttle and WOT air:fuel ratio (~12.5:1) from beginning of full main circuit startup to the red line. Load-dependent, not a varying air:fuel ratio that's rpm-dependent) shouldn't be necessary besides adding a bottom restriction if the boosters don't want to flow enough at WOT thru the mid-range or at maximum rpm... but I'm very highly doubting that (finding the correct (smaller than factory, I haven't much doubt) main jet will pan out in the testing of this)... because the annular boosters should be able to get busy and mix and vaporize the fuel and air well, and flow all sorts enough air:fuel with this and the combination of a smaller normal-sized main air bleed to create the flat stable higher loading and WOT air:fuel ratio, but not fire up before that unnecessarily... previous to those conditions can be easily and much more predictably and efficiently handled by the primary idle/transition circuit.

    Last edited by Walking-Tall; 07-11-2018 at 09:12 PM.
    Mike
    1986 Mustang convertible ---> BUILD THREAD
    Past Fox-chassis "four eyes":
    1983 Mercury Cougar LS
    1986 Ford Thunderbird ELAN
    1980 Capri RS Turbo

    Work in progress website ---> http://carb-rebuilds-plus.boards.net/

  10. #60
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    I had to read that like 5 times... lol

    I think some of it is starting to sink in though...
    '85 GT

  11. #61

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    Here's some more accurate juicy information for folks to sink their teeth into....

    Somebody at rfs posted a link to a good two-phase flow paper in pdf format online. Page 11 shows what an efficient, stable, and ideal homogeneous mixture of vertical two-phase fluid flow (just like in a Holley main well) looks like and acts like, which is what an "old school" Holley provides by default with it's design with minimal "emulsion" (sometimes only one 0.026-0.028" bleed at the liquid fuel level, and most commonly another about 7/16" below that), and usually a small 0.025-0.028" main air bleed to control the ultimate upper rpm air:fuel ratio, as well as contributing to the timing of when the booster will begin to flow.

    What you get with the "new and improved" excuses for carburetors out there nowadays, with swiss cheesed metering blocks with sometimes up to five comparatively giant "emulsion" bleeds (makes no matter even if they are all at 0.026-0.028"... there's too many, too much bleed air introduced), and a too-big main air bleed (because the too much "emulsion" has now convinced somebody the main circuit needs leaning because it's wicked rich down low and through the mid range... but alas, the big main air bleed will also make the highest rpm then too friggin' lean), as well as what I've read lots about with these 4180's that seem to frequently require more pump shot to eliminate some funny hesitation or off-idle stumble even when the float level and idle mixture and accelerator pump arm is right, and with a 0.028" primary idle feed restriction, which is big for a 600cfm on a stock or mild 302 engine, there's absolutely no excuse for idle/transition leanness... but then there's the primary idle air bleedS that are also oodles too big, and silly upside-down restrictive "emulsion" tubes in the passages to the base plate ... a whole lot of these WHY's is what's shown above in this thread... what you get is booster signal too-sped up or too-delayed, sluggish, spurting, non-homogeneous mixtures big clumps of fuel and clumps of air making their way to the booster and generating erratic air:fuel ratios all over the place. There's NO SUCH nonsense with an "old school" Holley main or idle circuit... the "new and improved" peddlers also insist on installing the primary idle feed restriction up near the idle air bleed, which generates all the same such erratic air:fuel ratio nonsense then within the idle circuit.... 'nuff said, lol... check out pages 12 and 13 for WHAT NOT TO DESIGN A CARBURETOR TO DO...

    Link to info --------------> http://notendur.hi.is/~halldorp/UNU/...se_regimes.pdf

    Last edited by Walking-Tall; 07-12-2018 at 09:23 PM.
    Mike
    1986 Mustang convertible ---> BUILD THREAD
    Past Fox-chassis "four eyes":
    1983 Mercury Cougar LS
    1986 Ford Thunderbird ELAN
    1980 Capri RS Turbo

    Work in progress website ---> http://carb-rebuilds-plus.boards.net/

  12. #62
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    Mike, can you post a link to RFS? Is it a "tech" site?
    '85 GT

  13. #63

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    Hey Steve. If you knew about "tuner", by your previous comment regarding possible explanation for the upside-down brass tubes out of the bottom of the main body, I thought you already knew about rfs, lol... racingfuelsystems... where there are nuggets of gold of explained, proven, logical and un-debate-able WEALTH of carburetor and ignition and vehicle-dialing-in information all over the place there, and some of the smartest, fastest, experienced guys on the planet, that, time and time again, help folks get their things working as best they can and better than ever by debunking and subverting all of the "new and improved" BS.

    The racingfuelsystems forum link: http://www.tapatalk.com/groups/racin...tems/index.php
    Mike
    1986 Mustang convertible ---> BUILD THREAD
    Past Fox-chassis "four eyes":
    1983 Mercury Cougar LS
    1986 Ford Thunderbird ELAN
    1980 Capri RS Turbo

    Work in progress website ---> http://carb-rebuilds-plus.boards.net/

  14. #64
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    Geez... It sucks getting old... I didn't make the connection to the acronym...

    I'm on there...
    '85 GT

  15. #65

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    Sometimes, yes, it's sucking to get old... lotsa good stuff too though

    Excellent, the racingfuelsystems forum is a great resource of very experienced and knowledgeable folks and information that money cannot buy... large amounts of money today certainly does not buy correctly working carburetors from the mainstream "makers".

    Thanks very much to you, Steve, "qikgts", for the nice condition primary float bowl that landed here this morning. Now if this Holley 4180 gets put to use where it's original application was, pre-'86 Mustang/Capri, or other, it'll have the option of sporting the correct float bowls with the extra large vent pipes that get connected to the vehicle's charcoal canister.





    ... I still haven't had a chance to get back to the primary metering block... I will, stay tuned...
    Mike
    1986 Mustang convertible ---> BUILD THREAD
    Past Fox-chassis "four eyes":
    1983 Mercury Cougar LS
    1986 Ford Thunderbird ELAN
    1980 Capri RS Turbo

    Work in progress website ---> http://carb-rebuilds-plus.boards.net/

  16. #66

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    Oh, and, the following is a more accurate and vertical locations' dimension-ed depiction of the proposed changes, of the equivalent to a traditional Holley's system of booster air correction, otherwise incorrectly known as "emulsion" or "e-bleeds":




    Last edited by Walking-Tall; 07-23-2018 at 08:20 PM.
    Mike
    1986 Mustang convertible ---> BUILD THREAD
    Past Fox-chassis "four eyes":
    1983 Mercury Cougar LS
    1986 Ford Thunderbird ELAN
    1980 Capri RS Turbo

    Work in progress website ---> http://carb-rebuilds-plus.boards.net/

  17. #67

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    Drilled and tapped the primary metering block as per the detail image in the last post :




    These tapped holes into the main well will all be plugged with 8-32x3/16" brass socket set screws. Same on passenger side :




    Tapped correct 6-32 thread depth between the main well and air well, and temporarily installed 6-32x1/8" brass socket set screws :




    Once all reassembled and with restrictions installed, this will be the equivalent to and behave like a traditional Holley metering block, as seen below, the lower two of #5 and #17 in the following image:



    Last edited by Walking-Tall; 07-23-2018 at 08:26 PM.
    Mike
    1986 Mustang convertible ---> BUILD THREAD
    Past Fox-chassis "four eyes":
    1983 Mercury Cougar LS
    1986 Ford Thunderbird ELAN
    1980 Capri RS Turbo

    Work in progress website ---> http://carb-rebuilds-plus.boards.net/

  18. #68
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    Nice work Mike! I wonder if anyone else ever has done this???

    A couple of requests when you get a chance... Can you show both sides of this 4180 metering block compared to the 4160 block? (Like in the same pic... Even just next to one of the other pics posted earlier would be good...)

    Can you do the same with the main body?

    How much more work are you thinking before it can be run?
    Last edited by qikgts; 07-23-2018 at 10:02 PM.
    '85 GT

  19. #69

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    Thanks, Steve. Not that I have seen in any detail anywhere...

    Might create more questions than answers, apples and oranges (refer back the thread for 4180 circuit pathways etc), but here are some comparison images... 4180 top, 4150 bottom:

    Main body primary (front) faces...




    Primary metering block front faces (wicked jet angles (4180's main wells more outward) - IFRs behind jets)...




    Primary metering block rear faces (wicked PVCR angles (4180's main wells more outward))...




    Whole lot of new/different/convoluted casting expenditure, but not a whole lot of reason, for all the 4180 differences...


    Traditional Holley circuits and locations of things:




    I'd like to be able to drill and tap the idle feed restrictions, and the power valve channel restrictions, so that their restriction sizes are adjustable, but the wicked angles with the 4180 block would necessitate drills and taps that are roughly twice the length that I have, or some long length drills/taps that I haven't ever even seen... so, the IFRs directly behind the jets will remain at 0.028", and the PVCRs at 0.049"... though I would really rather those PVCRs be adjustable, with the question of how small the main jets might be able to be...

    After all drilling and tapping, a real good cleaning and blowing everything out... then sizing and installing air bleeds, and restrictions for the above, and plugs everywhere necessary, and then get a kit (and regular power valve) and assemble and initial adjustments... whenever it is I'll get time again for all that, that is...
    Last edited by Walking-Tall; 07-24-2018 at 02:50 AM.
    Mike
    1986 Mustang convertible ---> BUILD THREAD
    Past Fox-chassis "four eyes":
    1983 Mercury Cougar LS
    1986 Ford Thunderbird ELAN
    1980 Capri RS Turbo

    Work in progress website ---> http://carb-rebuilds-plus.boards.net/

  20. #70
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    Very cool. Thanks for posting up the pics.

    I feel silly as I type this... Thus far you have only shown the front face of the modified 4180 block. Anything to see on the back side?

    Only asking because in this image...:

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    ...it looks like you can see through the 2 set screws (on the right), as if they were drilled through. Am I just seeing a reflection at the bottom of the set screws?
    '85 GT

  21. #71

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    There have been a few pictures of the back of the 4180 block, and no, there hasn't been anything new/different to see so far. Yes, you're seeing flash reflection down in those set screws. Those 6-32 set screws you see there are just blanks (not yet drilled with a restriction) that I temporarily install when I'm tapping for a certain depth so that their tops end up down flush to a surface when tightened. In this case, down flush, so they're not protruding out into the main well.

    Have a look at post # 66's image again. The blanks seen above are the brass you see on the right side of the main well here, with drilled connecting passages behind them that go to the main circuit air well (that I have drilled down deeper (1.500") to connect with these additions). None of any of this goes through to the backside of the block:




    The above is a depiction of the left end, the passenger side of the metering block in the following pictures:




    On the left of the top surface of the next image, left to right, are the idle well (not shown in the depiction), the big main well, then the main circuit air well:




    The angles of the jets and idle feed restrictions behind them, and the angles of the power valve channel restrictions really are ridiculously very small if they were to be measured with the front or back face of the metering block... a few degrees... not much... where the drill chuck bumps into things before you're able to complete drilling through into either the main well or the idle well... I stretched my drill bits and taps as much as I could, LOL, went slow and easy... and was able to drill and tap the PVCRs for 8-32 set screws. Now there's something new to see on the back of the block




    ... and for the factory idle feed restrictions, I was barely able but drilled through them where they were behind the main jets, then drilled the idle wells all the way through and out the bottom of the metering block (not ideal, but no other option in this case, and will be sealed back up good), then tapped up from the newly drilled bottom holes with 8-32 thread to a vertical height just below the center of the power valve's threaded passage (common traditional Holley submerged idle feed restriction vertical location), and then tapped 10-32 so that 10-32 set screws (and blue loctite) tightened will close up the bottom of the idle wells... and so, 8-32 set screws (primary idle feed restrictions will now be adjustable, for restriction size drilled in them, for adaptability for engines mild-to-wild) will get installed vertically from the bottom of the metering block, and then the idle wells' bottoms get closed down there with 10-32 set screws.




    So, this block will now be fully adjustable for all restriction sizes

    ... for the next Holley 4180 carburetor I deal with, it will be getting a regular traditional metering block adapted to it, instead of these extensive and intricate 4180 metering block modifications necessary to get around all of the 4180 "refinements" to establish efficient traditional Holley function and create the possibility of easy adjust-ability...
    Mike
    1986 Mustang convertible ---> BUILD THREAD
    Past Fox-chassis "four eyes":
    1983 Mercury Cougar LS
    1986 Ford Thunderbird ELAN
    1980 Capri RS Turbo

    Work in progress website ---> http://carb-rebuilds-plus.boards.net/

  22. #72
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    It took reading that first part of the post a few times to finally get through my head that the diagram you made was, as you clearly stated, the passenger side of the block. Geeezzzz...

    Thanks for all the pics and explaining the new work!

    Have you formulated a plan for how you would modify a traditional block to the 4180?
    '85 GT

  23. #73

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    Quote Originally Posted by qikgts View Post
    It took reading that first part of the post a few times to finally get through my head that the diagram you made was, as you clearly stated, the passenger side of the block. Geeezzzz...

    Thanks for all the pics and explaining the new work!

    Have you formulated a plan for how you would modify a traditional block to the 4180?
    By comparison to what we're doing, using a traditional primary metering block (or a traditional secondary block with no idle mixture screws) is ridiculously simple. Numbers 4 and 5 shown in the main body (top image) below need to be established. Number 5's are drilled so that the full length vertical idle wells within the 4180 main body can be blocked there...:






    ... a see-thru regular metering block gasket superimposed over where I've added the illusion of the above holes drilled to the 4180 body:




    ... then the idle and transition metering and the idle wells on the regular metering block are used, and idle/transition air:fuel enters the body's idle well with the number 4's. This is for keeping the idle mixture screws in the 4180 base plate, so the ones in the regular metering block would be closed/blocked, made inoperable.

    Vice versa could be done, blocking off the 4180 primary idle mixture screws in the base plate, and using the idle mixture screws in the regular metering block. The number 3 holes shown in the top body image in the 1st image above would need to be drilled, and vertically down (drilled up from the bottom of the body) from them in the body, out the bottom, and vertical drilling to a level below the throttle plates in the base plate to match those in the body, and regular idle feed discharge ports drilled in the throttle bores below the primary throttle blades... and new holes in the body-to-base gasket obviously required to connect the new vertical body and base drillings.

    Elimination of the 4180 accelerator pump transfer tube and o-rings can be done with an epoxied in length of steel tubing to meet flush with a regular metering block.

    Like I said, comparatively simpler... still some work though.
    Last edited by Walking-Tall; 07-29-2018 at 10:35 AM.
    Mike
    1986 Mustang convertible ---> BUILD THREAD
    Past Fox-chassis "four eyes":
    1983 Mercury Cougar LS
    1986 Ford Thunderbird ELAN
    1980 Capri RS Turbo

    Work in progress website ---> http://carb-rebuilds-plus.boards.net/

  24. #74

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    Tentative calibration of all, but specifically right now in regard to the approximate 200% more secondary transition air:fuel area that the much longer secondary transfer slots in a 4180 has. This will be addressed by adding secondary TSRs (transfer slot restrictions, in the same bottom-of-main-body (though obviously, out back for the secondaries) as the primary TSRs will be installed. Primary TSRs are only being installed, with restrictions that are 100% of the area of the primary transfer slots (that therefore do not restrict), for the option of restricting them if a grumpy camshaft that generates more manifold vacuum off idle/cruise than at idle is installed, for a "hot rod" that does not fit any current stereotype that the majority of folks think that stink rich etc is the "norm", a "hot rod" with idle RUMP that shakes the ground that can also be dialed in for maximum fuel efficiency) with a size restriction that is equivalent to what a typical Holley carburetor provides for secondary transition air:fuel for when the secondaries initially open.




    Secondary transfer slot restrictions installed won't likely (because we are also shrinking the size of the original secondary idle air bleeds), but may necessitate a slight increase in the opening of the secondary idle mixture screws in the base plate...

    As to other changes, please compare this chart to the previous one in the thread that lists the original sizes etc of everything.

    Last edited by Walking-Tall; 08-01-2018 at 11:39 AM.
    Mike
    1986 Mustang convertible ---> BUILD THREAD
    Past Fox-chassis "four eyes":
    1983 Mercury Cougar LS
    1986 Ford Thunderbird ELAN
    1980 Capri RS Turbo

    Work in progress website ---> http://carb-rebuilds-plus.boards.net/

  25. #75

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    ... don't have a #43 (0.089" - my numbered drill bit index needs a few missing, replaced, lol) drill bit for the primary transfer slot restrictions, so I drilled them with a #42 (0.0935") drill bit... no matter, they will be no restriction to the primary transfer slots' area...

    Had a bit of time... drilled the needed four 0.026" air correction bleeds, two 0.026" primary idle feed restrictions, two 0.028" primary main air bleeds and two 0.028" secondary idle air bleeds, two 0.046" power valve channel restrictions, two 0.074" primary idle air bleeds, two 0.074" secondary transfer slot restrictions, and the 0.094" primary transfer slot restrictions.


    Updated calibration chart:



    Mike
    1986 Mustang convertible ---> BUILD THREAD
    Past Fox-chassis "four eyes":
    1983 Mercury Cougar LS
    1986 Ford Thunderbird ELAN
    1980 Capri RS Turbo

    Work in progress website ---> http://carb-rebuilds-plus.boards.net/

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