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  1. #26

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    If you've got a 6.5 on hand, try it, it might not mind it. Test drive will tell. Again, potato, potawto, neither PV means anything unless you happen to press the gas pedal down into those vacuum levels and the primary main circuit is functioning (load/flow/rpm dependent) at the time.

    They have a small affect, yes, and a greater affect on transition if open more, sorta like transfer slots exposed below the throttle plates... (keep this in mind when thinking about this: within the idle/transition circuit, holes or slots above the throttle plate are air bleeds, and below the throttle plate is air:fuel feed) but more open secondary idle mixture screws or transfer slots below the plates would also have a greater affect on increased and unnecessary fuel usage at idle. Like other traditional Holley 4 barrels, a very small amount of secondary fuel is administered out of constant idle discharge ports that should have an approximate diameter of 0.020" (much bigger than that has a negative increased unnecessary fuel administering at idle) below the secondary transfer slots at idle in order that the fuel in the secondary bowl doesn't go stale if the back barrels rarely get opened... as well as keeping the secondary transfer slots ready with air:fuel to go into action when called upon by secondary opening. If there's an issue when the secondaries open... you either install a stiffer spring to open them later, or you modify how much transition air:fuel is getting to those transfer slots... because again, there's no pump shot out back, so pretty much any speedy secondary opening can be adjusted for with the right amount of secondary transition with idle feed and bleed sizing...
    Last edited by Walking-Tall; 03-20-2018 at 04:00 PM.
    Mike
    1986 Mustang convertible 3.8L ---> BUILD THREAD
    1983 Mercury Cougar 3.8L LS
    1986 Ford Thunderbird 5.0L ELAN
    1966 Ford Fairlane sedan 200-6
    1966 Ford Fairlane GT (390ci 4spd)
    1981 Mercury Marquis Brougham
    1980 Capri RS Turbo
    1971 Mustang Fastback
    1974 Pontiac Luxury LeMans

  2. #27

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    ... and because... curiosity... the E5Z 4180 here's body and block took a bath overnight and I've been crawling around in it's circuits some today, lol...




    ... and with the following additional circuit feed/bleed restrictions, some thinkin' is going to need to be done in order to fully understand which does what, when, and/or which or what is really necessary in the grand scheme of good function, and which or what would be best and easiest to make adjustable so as to be able to dial in primary transition for perfection with different vehicle combinations. I might be dealing with these for people now and then, so I want to know...



    I say equivalent below because the passages with restrictions there in 4180's feed both the primary transfer slots AND the primary idle mixtures screws... so, not quite the same affect as with traditional Holleys...




    More investigating and thinking required for the outer air bleeds down in the choke shroud shown below... they do not, but must, obviously connect with the idle circuit... there must be a cast horizontal passage (no external drillings obvious) down below them... anyway, weirdness, with small obviously connected with primary idle circuit air bleeds out front of choke shroud...




    ... and so sometime in a while, the complete mapping out and figuring what's what will commence ...
    Mike
    1986 Mustang convertible 3.8L ---> BUILD THREAD
    1983 Mercury Cougar 3.8L LS
    1986 Ford Thunderbird 5.0L ELAN
    1966 Ford Fairlane sedan 200-6
    1966 Ford Fairlane GT (390ci 4spd)
    1981 Mercury Marquis Brougham
    1980 Capri RS Turbo
    1971 Mustang Fastback
    1974 Pontiac Luxury LeMans

  3. #28
    FEP Power Member 85stanggt's Avatar
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    Interesting. I could not clean very far down into those air bleeds. I did take the brush and clean up in the transfer slot restriction tubes. I did not take the cap and plugs out of the metering block like you did. Do you think I have to do that or did my ultrasonic bath with compressed air suffice?

    I don't have a 6.5 valve. I could buy one. According to Holley's comparison chart, to replace the stock 2 stage PV, they recommend a 5.5 PV. 8.5 seems like it may come in too soon, but the 6.5 may be a nice medium (right in the range where my vacuum gauge showed) that give fuel a little later than the 8.5 but not too late like the 5.5 recommended or the 4.5 given in the kit.
    1985 Mustang GT Convertible
    Stock and original @ 213k, except for dynomax ultraflos.

  4. #29

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    The good ultrasonic cleaning and compressed air blasting well throughout all passages should suffice for you and yours that has been recently in use. I went in deep and am opening it all up because I'm thoroughly investigating these (sometimes notoriously troublesome) carburetors, so that I can fully understand what makes them tick and how to effectively modify them for better/best manners through adjust-ability... and besides, the rest of the carburetor here was (and still is) grubby enough for me to want to verify cleanliness inside everywhere since I'm just soaking to clean them here... there was a good amount of crap down the main circuit wells, but this one had been sitting for decades.

    Side note: in their infinite wisdom, they decided to use 5/16" cup plugs for the metering block's main wells, where all other Holleys use 1/4", so I'll have to search or improvise... and 1/8" lead balls in the four spots up top, which I'll close back up with 8-32 or 10-32 brass set screws... anything to be different, lol...

    Holley's brain dead suggestion to simply replace the two stage with a single stage of the same lower number... is just that, brain dead. By all means, try a 6.5, you may never sense any trouble issue with it again. Just sayin', if you're noticing struggle at all whenever the vacuum drops to about 10 or below, either upping the primary jets a number or two or opening the power valve any time thereabouts is right, and won't affect economy at all besides when at that load level and the mains are indeed supplying the fuel, which isn't usually often...
    Last edited by Walking-Tall; 03-20-2018 at 08:44 PM.
    Mike
    1986 Mustang convertible 3.8L ---> BUILD THREAD
    1983 Mercury Cougar 3.8L LS
    1986 Ford Thunderbird 5.0L ELAN
    1966 Ford Fairlane sedan 200-6
    1966 Ford Fairlane GT (390ci 4spd)
    1981 Mercury Marquis Brougham
    1980 Capri RS Turbo
    1971 Mustang Fastback
    1974 Pontiac Luxury LeMans

  5. #30
    FEP Power Member 85stanggt's Avatar
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    Ok so with further reading and a call to Holley, I learned some more stuff.

    The carb I took apart was definitely rebuilt at some time, but had been sitting for years due to its dirty condition. The PV that came out of it was stamped "25" for a PV that Holley says in their chart would equate to a 5.5" single stage PV.

    Calling Holley and giving them the 50265 list number of our 1985 4180c carbs, they looked it up and said that it took a "23" PV. That equates to a 6.5" single stage PV.

    Reading this post from JACook: http://vb.foureyedpride.com/showthre...=1#post1662930

    and this post: http://vb.foureyedpride.com/showthre...=1#post1844588

    Seems to suggest that from the factory, '85 Mustangs came with an "8" stamped PV, which according to 2nd link has a second stage opening of 4.5.
    The second link also says that the standard 3-1346 rebuild kits used to come with 2 stage PV that open at 10.5" and 6.5".

    So assuming that, my current carb rebuilt with a 3-1346 kit, I'm figuring (without taking it off the car and tearing it apart) has a 10.5/6.5 PV. So Holley says 6.5 and my last rebuild likely put a 6.5 second stage in there.

    It seems like it could use more in the 6-7 range, like that 6.5 stage is coming in too late. So I'm thinking maybe a 7.5 would do good without opening too soon like an 8.5 may. Then if the 7.5 isn't quite giving it enough, I can bump up the factory 622 jets to 64, which I do have on hand. That may maximize fuel economy while letting the car run with what it wants. How does that sound, or should I just throw the 8.5 in with the close-tolerance 62 jets and be done?
    Last edited by 85stanggt; 03-21-2018 at 01:17 PM.
    1985 Mustang GT Convertible
    Stock and original @ 213k, except for dynomax ultraflos.

  6. #31

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    If I'm understanding this right... the current carburetor on the car either has a 2-stage 10.5/6.5 PV, or a standard 6.5 PV... so regardless, alright, that and your findings of how it's running being the case, and you wanting to set up this fresh one you're doing to work well on the car in place of the other... although ultimately, this discussion is talking about the carburetor that's on the car... so in general, if it seems to be wanting more fueling in the vacuum range where either PV is fully open, then there simply is not enough total fuel (jets + PVCRs) available then in that window of loading. I still say choose whichever PV you want to for within that 7-10"Hg window, and I say put your #64 jets in it... because now this sounds like the PVCRs are on the small side and so are the factory primary jets, in the carburetor on the car... for the very different fuel we have today, or whatever... you'll have to best guess, take a stab at what you put in the "new" carburetor based on what we've discussed so far, and take 'er for a spin and under the same conditions and see what it does...
    Mike
    1986 Mustang convertible 3.8L ---> BUILD THREAD
    1983 Mercury Cougar 3.8L LS
    1986 Ford Thunderbird 5.0L ELAN
    1966 Ford Fairlane sedan 200-6
    1966 Ford Fairlane GT (390ci 4spd)
    1981 Mercury Marquis Brougham
    1980 Capri RS Turbo
    1971 Mustang Fastback
    1974 Pontiac Luxury LeMans

  7. #32

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    FWIW, the following is sound advice for choosing a (standard, single stage) power valve, and is very nearly similar to your vehicle's or most any stock/mild vehicle or combination's vacuum levels...




    (image photographed from the SA-Design book, "Volume One - Carburetors: Holley Carburetors", by Dave Emanuel, ISBN 0-931472-08-03)
    Mike
    1986 Mustang convertible 3.8L ---> BUILD THREAD
    1983 Mercury Cougar 3.8L LS
    1986 Ford Thunderbird 5.0L ELAN
    1966 Ford Fairlane sedan 200-6
    1966 Ford Fairlane GT (390ci 4spd)
    1981 Mercury Marquis Brougham
    1980 Capri RS Turbo
    1971 Mustang Fastback
    1974 Pontiac Luxury LeMans

  8. #33
    FEP Power Member 85stanggt's Avatar
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    Yeah that is great reference. It all makes perfect sense -- you just want to make sure the car has enough fuel throughout the range to handle its load needs.

    I'm digging through my old carb stuff and what I have from the rebuild of the carb on the car now (both of these are E5ZE-GA carbs). Out back in the secondary metering block I do have 77 jets. That's what's missing from my kit.

    Then I stumbled upon one of my threads from 2009 when I had the carb apart doing the secondary metering block mod. It seems like the stock secondary metering plate has a main orifice size of 0.076" (unconfirmed but seemed to be what I read somewhere back in the day). That would be the equivalent of a 71 jet. So I've gone up 6 sizes in the back. From 0.076 to 0.086. A decent jump but not insane. What would be more reasonable would be to put in 73 jets for a 0.076 to 0.079 jump. That is the same 0.003" increase as going from a 62 in the primaries to a 64. That'll probably be a great balance for today's fuel.

    Now, in that same thread, I also talked about the power valves. So now I know what is actually in the carb on my car without taking it apart. The rebuild kit came with a 2-stage valve stamped "5". The carb had a "23" PV in there before, and my extra parts 4180 carbs had PV stamped with "8".

    All of this matches perfectly with what was written in the power valve threads I linked previously. It seems from the factory '85 carbs came with "8" stamped PVs whose 2nd stage opened at 4.5". Maybe at some point things changed a little, because the 50265 list carbs Holley has having a "23" stamped PV. That was probably what was put in when they were rebuilt. The 23 valve was rated at 11/5.5. Of course, the Holley 2-stage to 1-stage chart says a 23 = 6.5 single stage. So maybe it comes in a little earlier than 5.5?

    Then the current PV from my rebuild kit is stamped 5. I have no idea what Holley part number that equates to to know what the stages open at. But the chart does say to replace with a 5.5.

    Bottom line the chart says 6.5 replacement for the stock rebuild replacement. And a 5.5 replacement for what's in there now. Go figure.

    Anyway, I've decided I'm just going to retune what I have on the car and keep this fresh one on the side. I had my fun rebuilding it.

    On the car I'm going to go to 64 main jets and 73 secondary jets and probably keep the current 2 stage valve that's in there and working ok. I think the jet increase will make up for the flat spot I have. From my old posts, I wrote it woke the car up, but I changed them back because I was a broke college student trying to save a buck on gas.

    I'm going to drive the car again and check the vacuum levels and then buy the right single stage valve to put in this rebuild I'm finishing. Then that'll be ready to drop on if ever needed.
    1985 Mustang GT Convertible
    Stock and original @ 213k, except for dynomax ultraflos.

  9. #34

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    Cool, should work good, keep us posted
    Mike
    1986 Mustang convertible 3.8L ---> BUILD THREAD
    1983 Mercury Cougar 3.8L LS
    1986 Ford Thunderbird 5.0L ELAN
    1966 Ford Fairlane sedan 200-6
    1966 Ford Fairlane GT (390ci 4spd)
    1981 Mercury Marquis Brougham
    1980 Capri RS Turbo
    1971 Mustang Fastback
    1974 Pontiac Luxury LeMans

  10. #35
    FEP Power Member 85stanggt's Avatar
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    Finally got around to this.

    1) Installed the 64 main jets in the primary and 73 jets in the secondary.
    2) I readjusted the float drop -- someone had told me years ago that the chugging around turns could be the float drop. Well I bent the tangs back to the same angle of the good carb I have -- made a difference for sure. Way more range in adjusting the needle and seat.
    3) replaced the single check ball under the accelerator pump squirter with the standard Holley check needle.
    4) replaced primary bowl gasket
    5) replaced fuel inlet gasket and needle and seat gaskets with nylon
    6) adjusted small choke cam screw to make sure car starts on fast idle (I had adjusted that down some for Florida, but it was too low and the car would stall because the choke flap wouldn't close all the way)

    Took the car for a short drive a couple days ago. The primary throttle response is great. There is no tip-in stumble that I could tell at all. It pulls nice at low RPM and feels more like it gained some torque down low. I also noticed I don't "feel" the secondaries opening anymore. Now, I don't know if that is a factor of the increased primary jets or decreased secondary jets. But up in the higher RPMs like 3k+, the car just doesn't feel like it has the pull it used to.

    Is that just because I don't "feel" the secondaries anymore or because it wants larger jets in the secondaries?
    Last edited by 85stanggt; 04-26-2018 at 07:44 AM.
    1985 Mustang GT Convertible
    Stock and original @ 213k, except for dynomax ultraflos.

  11. #36

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    If you "feel" when the secondaries open, that's a lean dip prior to the secondary main circuit going into action... Ford's calibration sizes are brain dead... if there isn't already a 0.028" secondary idle air bleed, that's what needs to be there... correctly dialed in, the secondary opening should be seamless. It might need larger primary power valve channel restrictions...
    Mike
    1986 Mustang convertible 3.8L ---> BUILD THREAD
    1983 Mercury Cougar 3.8L LS
    1986 Ford Thunderbird 5.0L ELAN
    1966 Ford Fairlane sedan 200-6
    1966 Ford Fairlane GT (390ci 4spd)
    1981 Mercury Marquis Brougham
    1980 Capri RS Turbo
    1971 Mustang Fastback
    1974 Pontiac Luxury LeMans

  12. #37
    FEP Power Member 85stanggt's Avatar
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    It's seamless now after upping the main jets to 64s. BUT it just doesn't seem to pull as hard up top since I dropped the secondary jets down from 77 to 73, which by all accounts is a fine size for the secondaries. Should I go back to 77?
    1985 Mustang GT Convertible
    Stock and original @ 213k, except for dynomax ultraflos.

  13. #38

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    Are you sure the secondaries are opening? A paper clip securely but loosely put onto the vacuum secondary diaphragm stem, up against the bottom of the diaphragm housing, and then going and doing some WOT testing, and then popping the hood and seeing whether the paper clip got moved down the stem some, is a way to check if they are opening, and how much they're opening as well. Unless somebody's enlarged the secondary main air bleeds too big (the E5Z 4180 here has 0.022" secondary main air bleeds), there shouldn't be a need for bigger than a 73 jet out back in a 600... double check float levels... and/OR, if you're able, can you tell me more about that secondary metering block? I'm asking because I'm also incredibly curious as to the sizing of orifices in those conversion blocks... such as idle feed restriction size, number of and size of the air correction bleeds (commonly incorrectly referred to as "emulsion bleeds")(because if there are too many or too big air correction bleeds, that causes early and rich WOT air:fuel ratios, and a leaner top end air:fuel ratio... the exact opposite of what's safe, and absolutely not the flat and stable air:fuel ratio over a wide range of rpm that is required for WOT), or are there flat top brass plugs in the top of the main wells (inners), etc?...
    Last edited by Walking-Tall; 05-02-2018 at 07:59 PM.
    Mike
    1986 Mustang convertible 3.8L ---> BUILD THREAD
    1983 Mercury Cougar 3.8L LS
    1986 Ford Thunderbird 5.0L ELAN
    1966 Ford Fairlane sedan 200-6
    1966 Ford Fairlane GT (390ci 4spd)
    1981 Mercury Marquis Brougham
    1980 Capri RS Turbo
    1971 Mustang Fastback
    1974 Pontiac Luxury LeMans

  14. #39
    FEP Power Member 85stanggt's Avatar
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    Holley sells the metering block as a modification to the 4180 to convert from the secondary metering plate to a metering block that lets you change jet sizes. I have no idea the bleed sizes. It's part number 34-6: https://www.holley.com/products/fuel...its/parts/34-6

    Probably overkill in a stock car, but at the time, I had knocking on heavy acceleration that I just couldn't track down, since everything from ignition to carb was correct. After talking on this forum years ago, some suggested the modern fuel was causing leanness on WOT that caused the knocking. That's why I bumped up the jetting. Of course, it probably would have helped to bump the primaries up also.

    Everything is probably fine. It's just that I don't "feel" the car pulling anymore, so it doesn't have that kick it felt like before. But that's a good thing, since it is likely now pulling through the RPM band consistently now.

    Once I get the interior back together, I'll have more time to drive it to really tell.
    1985 Mustang GT Convertible
    Stock and original @ 213k, except for dynomax ultraflos.

  15. #40

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    Yes, I know the conversion kits. What nearly angers me though is the dumbed-down emphasis of it all, such as not even displaying the back side of the metering block within it's marketing/advertising BS, the most important side of a metering block, as to judging wtf is going on with it, like idle feed restriction size and location, and how much "emulsion" they have going on with those.... Good luck with it, Please keep us informed.
    Mike
    1986 Mustang convertible 3.8L ---> BUILD THREAD
    1983 Mercury Cougar 3.8L LS
    1986 Ford Thunderbird 5.0L ELAN
    1966 Ford Fairlane sedan 200-6
    1966 Ford Fairlane GT (390ci 4spd)
    1981 Mercury Marquis Brougham
    1980 Capri RS Turbo
    1971 Mustang Fastback
    1974 Pontiac Luxury LeMans

  16. #41
    FEP Power Member 85stanggt's Avatar
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    Revisiting this thread. The 64 jets are doing nicely.

    Yesterday, I went and readjusted the idle mixture. I bought one of those flexible screw drivers off Amazon to help out (still not easy).

    Anyway, I started with the secondaries 0.5 turns out and the primaries 1.5 turns. Car wouldn't stay running at idle. Increased to 2 turns out on the primaries. That was better, but still couldn't stay running. I increased the secondaries to 1.5 turns and then it would stay running.

    Fine tuning between 1.5 and 2 on the primaries and 1.5 and 1.75 on the secondaries got me to a final adjustment of 2 turns out on the primaries, 1.75 out on the driver's secondary screw, and 1.5 out on the passenger secondary screw. If the two secondaries were equal, the car tended to "surge" a bit with the idle and vacuum dipping up and down. Why would that be?

    And should I spend more time trying to close the secondaries and open the primaries more? Does anyone know what they were set at from the factory?

    Also, I had 1.75 turns on the primaries, but when the hot idle compensator would open, it would make the car run rough and surge up and down. I guess that means I had the adjustment very close to optimal until the hot idle compensator would open and create a vacuum leak. The extra quarter turn on each primary seemed to solve that, but not sure if it is adjust too rich now.

    How are you supposed to set the idle mix taking into account the hot idle compensator?
    Last edited by 85stanggt; 06-22-2018 at 09:01 AM.
    1985 Mustang GT Convertible
    Stock and original @ 213k, except for dynomax ultraflos.

  17. #42
    FEP Power Member 85stanggt's Avatar
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    Double post sorry
    1985 Mustang GT Convertible
    Stock and original @ 213k, except for dynomax ultraflos.

  18. #43

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    The primary idle circuit in these is quite lean, with (IMHO, somewhat too) large idle air bleeds inside the choke shroud, and two additional smaller primary idle circuit air bleeds outside, out front of the choke shroud... The surge or vacuum dipping up and down at idle, a wavering or slight stumbling idle, is right at the too lean idle mixture point... which is how I initially adjust idle mixture screws... first by beginning with knowing both (primary, or secondary) are equally adjusted out, and then by slowly turning in each until that too-lean point, and then 1/4 turn out is usually close enough to right. Further finer tuning can be done if necessary.

    What is it's secondary idle speed screw set at? Did you set/adjust it? The secondary throttle plates within a vacuum secondary that's on a stock or mild engine never normally need to be open more than just so that they do not stick shut in the throttle bores. I usually set them to a default 1/4 turn open... and the adjustable (after removing tamper-proof plugs) secondary idle circuit's necessity in these (stock, mild, or even rowdy-cammed) vehicles is questionable at best IMHO. The back idle mixture screws only really need to be very minimal turns out... like a set-and-forget 1 (or less) turn out... and then the tamper-proof plugs could really be hammered back in. Concentration on the primary idle speed and mixture is all that needs to be adjusted for smooth and lean-best engine idle.

    Hot idle compensator?... I'm not aware of any such animal on these... you mean the idle speed solenoid?... I'll wait to make further comment until after those answers... but briefly as a test, get it to that surging dipping point, and block the outer idle air bleeds with your fingers and see if that smooths things back out...
    Last edited by Walking-Tall; 06-27-2018 at 12:47 PM.
    Mike
    1986 Mustang convertible 3.8L ---> BUILD THREAD
    1983 Mercury Cougar 3.8L LS
    1986 Ford Thunderbird 5.0L ELAN
    1966 Ford Fairlane sedan 200-6
    1966 Ford Fairlane GT (390ci 4spd)
    1981 Mercury Marquis Brougham
    1980 Capri RS Turbo
    1971 Mustang Fastback
    1974 Pontiac Luxury LeMans

  19. #44
    FEP Power Member 85stanggt's Avatar
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    So the secondary stop set screw is set to about 1/4 turn. I backed it out until the secondaries were seated and then turned in until it touched the tang, and turned an extra 1/4 turn. So they are barely open. BUT, if I turned the mixture screws to only 0.5 turns out, I would have to open the primaries up to like 3 turns. It seems more balanced to do the 1.5 turns on the secondary and my primaries out to 2. The surging really happened when the primaries were at 1.75 turns. The extra 1/4 turn like you said evened things up a bit. I may increase it another 1/8 turn to smooth it out more.

    The hot idle compensator is built into the metal PCV tube going into the base of the carb. It is a thermally-activated, metered vacuum leak that opens when the underhood temps increase, in order to increase the idle thus increasing airflow via the fan. So as I was adjusting, the standard idle would be pretty good until that opened and let in more air. It's running good now after I increased the turns, but I didn't know if there was a known procedure to use to compensate for it. I'll have to pull out the Ford books and take a look.

    Lastly, there is one thing I would love to figure out with the carb, that my previous one didn't seem to have an issue with. When the car is full hot, it won't start unless I crack open the throttle with my foot. That goes for whether I turn it off and right back on or leave it for 30 minutes. And I should clarify that it will catch and start, but dies right away unless I work the throttle. The '83 carb that was on there before never had this issue -- I would bump the starter and boom it would start and run right away. I'm under the impression this is fairly normal for a hot carb'd car, as I've been told on here before, with percolation and all. But I figured I'd ask, because I feel like it's a problem of too little fuel rather than too much, but I'm not sure.
    1985 Mustang GT Convertible
    Stock and original @ 213k, except for dynomax ultraflos.

  20. #45

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    Perfect. Yes, again, the necessity of greater than the usual minimal amount of secondary idle air:fuel is due to the leanness of the primary idle air:fuel calibration, IMHO... so certainly, whatever works best, leanest, smoothest for your factory calibration 4180 situation, is what's right.

    Oh, okay external to carburetor, gotcha. Again, shows up the borderline lean, touchy primary idle circuit calibration. I guess you'll have to split the difference between when there's no extra air to when there is the metered vacuum leak... although, I wonder at what temperature... because idle speed and especially idle mixture is a waste of time trying to adjust until after the engine is fully warmed up, because it will always be too rich then when warmed up...

    We have to live with varying percentages of ethanol in gasoline today. Thanks so much, gubment and lobbying jackasses. Alcohol's boiling point is much lower than old school gasoline's, and so yes, percolation may well be bubbling up some in the main wells and adding a drop or ten, or at the very least increased fuel vapors at the throats/boosters... it's not normal, but sometimes today's version of normal. Street car today = heat in the intake manifold is good, and some to the whole carburetor is fine, but anything done to minimize searing heat from getting at the float bowls and metering blocks is an even better thing. In general, when the idle speed and mixture is right, even today, a good running up to temp engine with a carburetor on it with cool fuel in it and the choke open still only takes a bump of the key, standing beside the car reaching in the window, to start and run. That's how my Mustang acts, and all else "old school" I've had my hands on rebuilding/building a carburetor for, and with the Mustang, reliably/repeatably for 2+ years now since adding the Holley 500 2-barrel and Duraspark II.
    Last edited by Walking-Tall; 06-28-2018 at 10:54 AM.
    Mike
    1986 Mustang convertible 3.8L ---> BUILD THREAD
    1983 Mercury Cougar 3.8L LS
    1986 Ford Thunderbird 5.0L ELAN
    1966 Ford Fairlane sedan 200-6
    1966 Ford Fairlane GT (390ci 4spd)
    1981 Mercury Marquis Brougham
    1980 Capri RS Turbo
    1971 Mustang Fastback
    1974 Pontiac Luxury LeMans

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