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Thread: Dual Intake Manifold Thoughts

  1. #1
    Junior Member Bart's Avatar
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    Dual Intake Manifold Thoughts

    I know that there have been a few in the past that have tried a few different styles for trying to install a dual carb intake on the 4A084, but in looking through many of the threads, on this forum and other places, there are a couple of directions that I haven't seen anyone talk about.
    the recent postings about the intake mods, on installing the solex carb, has got me looking and trying to learn just a little more.
    I have been going over a lot of the postings about the carb mods on the VW motors, to see what works, what as been tried, and what ideas have fell by the wayside after a couple of years. there is not a lot of new improvements past the mid 1980's due to the rise of fuel injection.
    but there is still a big following and many ideas that are still being floated around. for the carbureted VW motors.

    one item that the VW motors have incorporated is using the exhaust gas tube to heat the intake manifold, they have this for all the carb setups where the carbs are located in the center of the motor. to keep the icing under control,

    on the 4A084 motor, the only 2 methods that I have seen, are to use the breather line that is routed in the stock rubber intake. or to incorporate a breather box, that will draw warmed up air off of the exhaust manifolds.

    back to the intake ideas, I have a couple of different ideas that I am thinking about.
    one is to take the intakes off of the 2A042 motors that I have, and run two carbs, one off of each.
    I attached a couple of pictures of what it looks like, there is 6 inches between the center of the intakes, which will leave clearance for some EMPI 34 carbs, if I decide to go that route, or fab up a couple of 90's and install the mukuni carbs that I have on hand.
    the one item that I will need to be looking at is some good bracing for the intakes, where I turned them pointing upwards, the factory bracing doesn't really work now.

    I did purchase couple of intake joints from Saturn Surplus and an thought, is to go along the route that Papee has,
    but install a 1-3/8" 90 degree elbow, that will feed into the intake. and install a single Mikuni carb. to that

    an other idea is to modify the intake joint, so that I could install, an weber /empi 32/36 progressive carb, or an Holly Weber 5200 double barrel carb that is used on the 1.6 liter motors. it is with these styles, that I am finding out that they like an heated intake manifold. don't know if I would need to build a little shroud between the intake joint and the motor, to capture heat off of the motor, still thinking of what would /could work to keep the intake warm.
    I am looking this style, yes they will use a little more fuel, but I like the thought of having an carb with a primary and secondary throttle body. it is a carry over from my younger years, of opening up the secondary's in my brothers 69 GTO, and watching the watching the gas needle drop.

    any way, these are just a couple of ideas, and things I have been thinking about, and will be looking as my budget will allow.
    I am seeing the need to install at least 1 or 2, O2 sensors when I get this going, so I can know what the motor is doing.
    but I do enjoy tinkering with this project, and it is fun to see where it will lead.
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  2. #2
    Super Moderator Corky's Avatar
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    Re: Dual Intake Manifold Thoughts

    Hi Bart..

    I like the split intake design you've posted...Definitely a cool factor if not anything else...Here's some general thoughts on running multiple carbs on these engines...You need to be careful about overcarbing the engine from two perspectives...First up is too much fuel for any given RPM...For the sake of argument using the EMPI you'd need to cut the jet sizes in half seeing how you're only feeding two cylinders instead of 4..Not too bad of a situation to overcome......Which leads us to the next issue...Air velocity...I'm not sure if the EMPI will respond correctly to only 2 cylinders worth of suction...If by chance you'd get the carb to work there may not be enough of idle air velocity going past the venturi to keep the mix in suspension...Or have a nice transition from the idle circuit to the main feeds...

    Definitely a lot of experimenting would need to be done...Don't forget the need to set up the carbs to pull the vacuum evenly using gauges similar to setting up dual 4bbl carbs that both have idle circuits,,,

    IMO I'd start with 2 carbs that are half the size of the EMPIs to keep the air velocity up if I were going to use the design you've posted with a stock engine...Now, if you were to have a camshaft welded up/reground for more lift and duration that's a different story..

    Funny you mention the VW heat tube.....I've got a VW intake with the heat tube in my stash of parts for 084 experimenting... I was going to simply weld the tube on a header primary tube using opposite sides of the engine and pick the cylinders according to firing order so they would somewhat scavenge each other to keep the flow pulsing back and forth to deliver heat...How much flow would create too much heat would be the trick but the tube itself isn't that big to begin with....I'm a holley carb guy and I've got a holley bugspray carb and that intake for future experimenting after the baseline tests...

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  3. #3
    Administrator Papee's Avatar
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    Re: Dual Intake Manifold Thoughts

    Great idea on the vertical carbs. It never crossed my mind when I was messing with it. I got in my mind to use the mukinis and never thought farther. My problem was designing something everyone could use running direct drive or redrive. The vertcal carb will fix some of those issues.
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  4. #4
    Junior Member Bart's Avatar
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    Re: Dual Intake Manifold Thoughts

    Corky
    it is good to hear some of your thoughts,
    last night I thought I would compare the carb off of the 4A084 to the carb off of the 2A042, just to see what the differences are. thy are a simple carb, but I may not have the correct terms for parts I will be talking about. in the pictures posted below the 4A084 carb will be on the left, and the 2A042 carb will be on the right.

    the carb bodies are the same, both are # 13206E1170, on the top of the 4A084,there are the numbers stamped 13620 20hp. and on the top of the 2A042 it is stamped 13619 10 hp

    (4a084 ) are the first numbers, (2a042) are the second numbers
    metering suction rod (084)outside dia. .093 in. (042) .1225
    inside dia.(084) .0550 (042) smaller than3/32 (.0938), larger than 5/64(.0781)
    suction hole on bottom side dia.(084) .0420 (042) .0465
    feed hole on top by threads (084) .0225 (042) .0420

    well nut (084) 3 holes at .0380 (042) 4 holes at .0465

    I used drill bits that were available to find the closest size
    to get these small numbers I used a drill set from https://www.king-tool.com/storefront...products_id=38
    king tool set # KTD01
    when I first laid out the parts for both carbs out on the table, I was kind off puzzled as to why there would be bigger holes in the fuel metering rods on the 2a042 than the 4a084 carb, I mean you are only feeding 2 cylinders, why would you want more fuel?
    with Corky's statement about having a smaller carb and smaller jetting, it appeared that Zenith went the opposite direction.
    that is until you start looking at the air flow comparison.
    I am assuming that Zenith for cost, kept the same carb body for both motors, and with the 4A084 motor sucking twice the air volume, went to using smaller holes to meter the correct amount of gas for the greater air volume and suction. a least that is what I have came up with at the moment.
    so I feel that I may need to use this comparison, at least I see an starting point to go from. if I decide to try two separate manifolds.

    Corky if I am correct, on your car, with the 3 deuce intake manifold setup. is the air plenum interconnected between all 3 carbs?
    and from that set up. you have learned some very important concepts. that many of us over look and forget.

    I have a ways to go before I can start testing anything, an develop any learning curve, but I would like to hear what your ideas are on some of these
    I still need to look and see what the VW people have done when they split there motor in half for jetting purposes,
    I enjoy learning and trying to understand how to resolve and make things like this work.
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    Last edited by Bart; 12-11-2016 at 08:57 PM.

  5. #5
    Super Moderator Corky's Avatar
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    Re: Dual Intake Manifold Thoughts

    Great info Bart...Keeping the carb body the same would make it easy for Zenith to make the parts fit a wide range of applications...I think you're spot on ...Reduced airflow means adjusting the orfices to get it working properly...The 042 still has the same port size as it's big brother so it makes the most sense and evidently there's enough velocity past the venturi with 2 cylinders to keep the mix in suspension...

    Yes most of the musclecar era automotive multi-carb intakes have a central plenum...Strangely enough even with a central plenum all three holley carbs{ford,chevy and mopar all used them at some point} have an idle circuit...The center carb is the workhorse and the car technically runs off the 2bbl until the throttle is tramped...Then the two end carbs both come in at the same time...And back in the seat you go !!


    The whole problem I see with the 084 is the small cubic inches of the engine narrowing down the choices of carb selection...It's real easy to over carb the engine and loose either bottom end response or top end performance..

    With that being said it's a brand new territory and there's no right or wrong way to go...The guys that have experimented with them don't seem to have the trial and error info readily available for others to take to the next level...I've searched and searched for any actual reference numbers and/or parts that have been tried and have come up with nothing other than the same info that's been thrown around here...

    In any case you'd need something in place to check what the engine is doing not just blindly adding parts and have the engine burn a piston or grenade in short order from something that could have easily been monitored...

    Let's face it most guys building a mini aren't going to spend alot of time or money in research and developement.. The majority of mini builds have been sent down a path for being home built and cheap...... Most want to "get it done and get out there as soon as possible"..and that's fine it gives more an opportunity to get into a hobby that they may not be able to afford otherwise...Unfortunately that usually means taking the quick, easy and safe way out of a situation and copy a modification someone else has done and had luck with...
    Some of us are not content and need to tinker with stuff just to see if something can be gained...That would be us...

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  6. #6
    Super Moderator Corky's Avatar
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    Re: Dual Intake Manifold Thoughts

    Speaking of multiple carbs Papee was going to use the tillotson "274 mule" carbs but was'nt sure how to orient them on the engine...I thought those had the best chance of working "out of the box"...For a quick and easy kit....They were for an engine half the size of the 084 and even has an accelerator pump !! Here's a simplified configuration of how I was going to make a trial run with those carbs...Basically the intake ports would be equal measurements and use the cylinder's offset as an advantage...Then use a central bellcrank much like the old mopar Max Wedge engines used...the carbs would end up facing outward allowing for a scoup style air cleaner to catch the passing air from the sides...
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    Last edited by Corky; 12-11-2016 at 09:01 PM.

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  7. #7
    Junior Member Bart's Avatar
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    Re: Dual Intake Manifold Thoughts

    it has been fun reading and learning more about the dual carb set up. there are so many different and what if, variables to take into account.
    just changing the lengths of the intake tubes, will change the jetting so and power curve of the motor, and it can be just the simple things that are often overlooked. one thing I learned that was kind of interesting, was just the normal expansion of the motor as it heats up will affect the linkage adjustment, when having a dual intake like what Corky posted, but in reading many of the VW forums, this style is a lot more user friendly than having the center mounted dual carbs. (at least I am seeing a bigger push by the aftermarket venders leaning that way,)
    there are a lot of ideas and different directions that a person could go. and it will be a learning process, hopefully in a year from now I might have something that works.
    the pros about using the 042 dual set up, is all I need to do is purchase the carbs figure out what carb settings need to be, deal with a little intake manifold icing issue. (which may only need to draw air from the crankcase to both of the air filters. and be done.
    but then if I every want to add a redrive, my rear carb will be in the way.

    the more I look at fabing up a short intake, and adding a dual carb set up. like Papee's idea above. it might have a lot less head scratching, in the end. than using a dual stock 042 setup,
    I found a setup on JBugs web page. http://www.jbugs.com/product/47-7401...rburetors-kits
    where they listed the carb jetting and set up for the short intake.
    but which route, I take this, it will be fun to learn what works and what doesn't.

  8. #8
    Junior Member Bart's Avatar
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    Re: Dual Intake Manifold Thoughts

    almost done with a adapted intake for the 084 to use with an empi /solex 34 PICT carb. just need to finish the adapter flange plate.
    l learned a couple of things, but it turned out overall not to bad, I still need to make an adapter plate to change the bolt orientation, for bolting on a solex carb.
    also if you weld the upright stub, before cutting the hole out, make sure that you have a long enough hole saw that will reach down far enough to make the cut all the way, a normal hole saw will start to make the cut, but the hole saw mandrel will hit the top of the carb throat. letting you only make the cut a 1/4 of the way through before it stops on the top of the carb.
    but it was a lot simpler to weld it before making the cut, with using the tig to weld, the impurities of this cast aluminum was not that bad, a good cleaning with a SS brush, sprayed down with acetone, before attempting any welding, it was interesting on how much black contaminates came off the casting with the acetone, and that was after it was brushed really good
    also i should have cut out the hole, before welding the front cap on, ended up using an extension on a end grinder to get the flap wheel down in the throat to clean up the cut. it would have been a lot simpler to clean up some of the burs by going through where the front was cut out.
    I left it with the tab on the side, so it would be inline with the original mounting bolt, might make it simpler to attach it to a bracket with it orientated that way,
    I made a couple of elbows to attach a mikuni side draft carb, on the base I left it large enough to have multiple holes so could change the facing direction of the carb.
    but I am not liking how much further it extends the carb, I probably will put another intake joint together with and 90 degree elbow, which will bring the carb a lot closer, and still raise it up enough for the float bowl to have clearance.
    and if I want to attempt using the dual 042 set up like what I have pictured above, I will modify those intake joints also with an 90 degree coming off also,
    I am just slowly working on getting an assortment of things together, for me it is a lot easier to try to assemble it, to see what and if it will work.
    on the 042 intake joint I can see it would be very easy to cut off the upright stub, and weld an base plate on it, so I could change the direction of the carb, where there is only 6" of clearance. if I go with the mikuni carb.
    I am still going over a lot of the VW web pages, to see if anyone or vender has a set up, for the solex 34 pict carbs in a dual center mount configuration. from that I might have at least an starting point, to begin with

    and see what they have set for the base carburetor settings.
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    Last edited by Bart; 12-13-2016 at 02:48 AM. Reason: adding more details on items learned

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    Super Moderator Corky's Avatar
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    Re: Dual Intake Manifold Thoughts

    Bart that's some great craftsmanship there...Good job !!! Now you've really opened up your options for fuel delivery...

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    Re: Dual Intake Manifold Thoughts

    Quote Originally Posted by Bart View Post
    I probably will put another intake joint together with and 90 degree elbow, which will bring the carb a lot closer, and still raise it up enough for the float bowl to have clearance.
    Hi Bart, I would use the sweep elbow that you have fabricated. You don't need another hard right angle elbow in the air flow. kent

  11. #11
    Super Moderator Corky's Avatar
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    Re: Dual Intake Manifold Thoughts

    Quote Originally Posted by kent View Post
    Hi Bart, I would use the sweep elbow that you have fabricated. You don't need another hard right angle elbow in the air flow. kent
    And while we're on that subject ....I know the intake elbow conversion has proven itself to be the best option for performance and ease of modification on the factory intake joint...I would'nt mind trying to take it to the next level...For me that would mean getting an extra set of intake runners and cutting them in a way that would bring all 4 together in sweeping 90* uprights making their own "central plenum" as they join...In other words,bring them all together cutting the internal walls out between them at a certain point...Then weld the solex adapter plate on top{think header merge collector}...No harsh corners,no place for fuel puddling in cold temps,and theoretically a smoother run through all RPMs..

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  12. #12
    Junior Member Bart's Avatar
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    Re: Dual Intake Manifold Thoughts

    i am waiting for another shipment from saturn surplus, for the 084 motor they only carry tubes for the #2 and #3 cylinders, and for the 042 motor the tubes are used, but with out a tubing bender for the 1-3/8 intake tube, their price, you cant beat it.
    Kent, i was looking at using the short sweep, in trying to keep the total length shorter, i forgot to think about the obstruction that tighter sweeps do to the air flow.

    i have been looking at a couple of options to put together this winter, and think i will have at least 3 options to choose from when i am done,
    i was real excited about purchasing the dual intake kit in the link above, until i realized that the carbs they have in the kit don't have a choke. but at least they list all the jetting needed for that application. so it would get me in the ball park, maybe. i may have to purchase a dual carb set up in pieces. i just cant see having carburetors with no choke.
    building the dual intake for cylinders 2 & 4 should be very straight forward, but on the other side the push rod tubes on cylinders 1 & 3 are going to take just a little more thought.
    it will be keeping the tubes the same length, that will be the most challenging.
    that is an interesting idea, to add a little more to them, and sweep them up into a custom manifold. still trying to come up with an simple method of applying heat to the center manifold. i was reading on a tech page in aircooled.net, that some, instead of running exhaust gas through the center intake manifold, would divert a oil line through it instead. but they warned that if you purchased a cheap intake, that because of its porosity, oil could leak into the suction side.
    this might be an simple way to keep a dual center mount intake from icing up.
    we will see how much i get done on it, with family coming home for Christmas, I cant believe it 6 more days, and we are at the shortest day of the year, the sun is coming up around 9:30 and disappearing behind the mountain at 4 in the afternoon, just wish i had heat in the shed.
    i am having fun just thinking about some different ideas, and methods to run the intake, and try to take it a little further, maybe they will work, and maybe not, but using some of Corky's ideas, i might be able to get it dialed in.
    an other web page that i have been looking at
    http://www.aircooled.net/vw-carburet...selection-101/
    there is quite a bit of useful information that i think will help me get things dialed in on this motor also. at the bottom of there web page, if i understood it right, they gave permission to link the page, but not to publish it. I don't want to get this forum in any trouble by posting the link here.
    Last edited by Bart; 12-16-2016 at 03:43 AM.

  13. #13
    Super Moderator Corky's Avatar
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    Re: Dual Intake Manifold Thoughts

    Bart, you wouldn't necessarily need to plumb the oil "through the manifold"...What about passing the line under,along the central plenum area as a separate passage...
    My concerns are not knowing the limitations of the factory oil pump and just where to "bleed off the pressure" without possibly dropping the working PSI too much...We had talked briefly about this in Papee's turbo build thread...Using the unused{as in blocked off} governor oil port for an oil lube line...Which wouldn't be a bad thing for a turbo with limited bearing clearance keeping the lube line pressure up compared to running an unobstructed oil line from one area of the engine under a manifold and simply returning it at another point...

    I realize you're up there having frosty the snowman as your helper and you need that manifold heat to keep out of trouble and get home every time in frigid temps...So what about using the oil temps in a different way...You need an auxiliary oil cooler correct ??? Why not run the hot oil coming from the engine block up and through a metal passage/sleeve/heat exchanger{under the intake manifold} as it's heading to the oil cooler ?? Now you're eliminating any concerns with an additional burden/bleed off on the oil pump and you're helping dissipate the oil temp before the cooler does it's job...

    There's a few way's to get it done coming to mind...A metal tube using barbed ends so you can run rubber hose from the block to the intake then from the intake to the cooler...Another way would be to add nuts/flairs to the ends and connect fittings...The tubing could be aluminum welded to the intake...Even steel "soldered" to the intake joint for heat exchange...

    Just thinking out loud throwing some ideas around for you...

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  14. #14
    Junior Member Bart's Avatar
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    Re: Dual Intake Manifold Thoughts

    you are on about the same thoughts that i have been tossing around.
    i keep reading about, that some still have the carb icing up every once in a while.
    i was going to wait until i made something up. kind of like show and tell.
    but i still am working on some of the mods, and on the intake that i made up. i may not have enough clearance for the linkage on the empi 34 pict. that is at the bottom of the carb. so i don't want to put the cart before the horses.
    so my thoughts are to coil some tubing around the intake body, but i need to turn it into something like a heat sink. and with the bare lines being in the open, it may or may not disparate the heat to where i am wanting it.
    so once it is wrapped i will use something like Splash Zone epoxy, or an aluminum putty. and mold or cover the lines that are wrapped around the intake.
    i would leave the ends coming off of the intake with compression fittings, the inlet side would connect with the oil port that fed the governor, and the return line could go a few different places. there are a couple of ports that are on the front timing gear cover,
    (the 2 ports that are plugged next to the hot air carb suction line, will not work, they are on the same side of the reed valve as the port that sucks warm air to the carb. scratch that idea.)
    or could always drill and tap a fitting on the plate that blocks off where the governor used to be.
    i may put in an 1/4" ball valve, so i could regulate the temp. (don't want to have vapor lock)
    also thing of some short flex lines, which could help out with any vibration.
    i just put on a picture of something it may look like just using tygon tubing.
    i tried some 1/4" SS, but that doesn't bend so easily,
    the simplest option would be to use 1/4" soft copper, which should form nice and snug against the intake.
    cover that with some splash zone or aluminum putty for the heat sink effect, and should be good to go
    , i may insert a temp probe against the intake manifold. then i would know if this will actually work, or if it is a pipe dream. ( as Papee would say, by the time i get this going, i will be needing an instrument panel that is at least 4' x 2')

    any way this is just one of the few ideas that i am toying around with on the 084 motor,
    received, some odds and ends, intake tubing from Saturn Surplus today, just waiting for intake adapters and other trinkets, and see what i can come up with. been going over quite a few of the older posts, where much has been discussed about different carbs and intakes (and the lessons learned)
    and i hope that in the near future that i can share some good data,
    if this works or not.
    for the moment the 084 motor will just be on a stand, until i widen by boat hull, maybe i am not the daredevil that i used to be, but i will feel a little more at ease when i add at least 1 foot to the width of my little boat.

    Just took apart the governor, and it is a 1/8" hole that feeds into the bottom bushing, will post pictures later, there is some good resistance, when trying to blow through it,
    Corky, you are correct again, if I used this line, I would have to turn down the bleed off, or I would see a good drop in the oil pressure,
    Back to the drawing board,
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    Last edited by Bart; 01-08-2017 at 02:14 AM.

  15. #15
    Super Moderator Corky's Avatar
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    Re: Dual Intake Manifold Thoughts

    I checked the flow of the governor as well some time back...There's more restriction there than I had originally thought...The adjustable flow is a great idea then you'd be able to keep the vapor lock in check if there's any happening in warmer temps...As long as you have a restriction at the end of the line..Say, a carb jet or something similar you should be fine...And if you do go the governor oil port route you could insulate all other areas of the line to make sure you're not loosing too much heat to the exposed areas of the line...

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  16. #16
    Junior Member Bart's Avatar
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    Re: Dual Intake Manifold Thoughts

    coming up with ideas that may or may not work, is something that I enjoy doing. I thought I would put in a couple of pictures of what the oil weep holes in the governor look like, there is a about 1/8" hole for the inlet, the governor shaft has hole drilled into it that lines up once every rotation. which sits in a brass bushing.
    it has an outlet hole about 1-1/2" up the shaft that lubes the inside of the rotating flyweight shaft. which will allow the governor to spin freely on a film of oil. without being able to start my motor at the moment. I am trying to come up with a method to pressurize the incoming line on the governor with oil and just see how much oil will come though in a given minute. (another test to do sometime).

    also it is simpler to use some tygon tubing for a visual, to get an idea on how I want to wrap the soft copper tub around the intake.
    I am going in quite a few different directions on this motor, with the intakes, and exhaust. hoping that in a couple of weeks I will be firing it up.
    and then the real R&D will come into play.
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  17. #17
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    Re: Dual Intake Manifold Thoughts

    Fascinating reading Gents ... I might interject that carburetor icing may not be as big a problem as you might suspect with the Solex conversion. Since I modified my spider and went with the 34-PICT carb I have not experienced significant icing in any weather, cold or hot, even at WOT.

    The issue I see with having continuous air heating in the intake is that you may loose some HP. There's something to be said for cold (dense) air. In my aircraft, whenever you add carburetor heat your manifold pressure decreases and you loose some thrust. With my 084 the only heat I'm adding is from the crankcase breather via hose into the air cleaner. JMO.
    11'6" Marty Bray Hull
    4A084 Continental
    Circle "S" 1.69:1 Reducer
    67" Whirlwind Razor X Prop
    SS Rigging

  18. #18
    Administrator Papee's Avatar
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    Re: Dual Intake Manifold Thoughts

    Same here with the conversion, I've had some sweating but no icing.
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  19. #19
    Junior Member Bart's Avatar
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    Re: Dual Intake Manifold Thoughts

    that is good to know that just the change in the intake and carb. would make that much difference, maybe I just worry a little to much about some of this stuff.
    lot of it is, in the fall when I know I will be out and about, the weather usually is in the 30 to 40 degree range, and most of the time raining to beat the band. so that is why I am looking at some options.
    still looking at putting together a variation or two, of a double intake. just to see if it may work. still trying to look and see what is the most user friendly, and what kind of sweeps I want,
    it is simpler to use the short sweep 90's. it looks like there may be enough room to trim the intake tube and make it fit.
    but looking at using the long sweep 90's, there isn't enough room, for a smooth flow with the intake joint, with out making compound cuts, and having the intake joint look more like an upside down Y, just playing with cutting broom stick handles to get a good layout for a compound cut.
    it makes it simpler fabing up a jig.
    I am learning to make a mock up, and think about where I want it to end up. before I start making to many cuts.
    at least is keeps me out of trouble.
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  20. #20
    Junior Member Bart's Avatar
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    Re: Dual Intake Manifold Thoughts

    I really didn't like how the fit up was looking on the last couple of pictures, with trying to keep from cutting the intake joint. with 6" center to center, it doesn't leave a lot of room before you get to the elbows,
    ended up making some paper cutouts for different angles that I could use to make it a little more user friendly,
    ended up liking the lines at 75 degrees,
    with a few bosses that were cut off at the weld, I have been trying to use them in with the intake, it is just so much fun to make this go together with 6 loose joints. that was with the first attempt.
    sitting back and looking at this, the first one , and all the scrap pieces, (note to self, a hack saw is the only way to cut the tube.) I was getting a pretty good bone yard with pieces that were just a little to short. (If I do this anymore a tubing bender with 1-3/8" dies would make life so much nicer,) another Christmas wish list item.
    anyway with one proto type, to look at, there were 2 different intake tubes with the correct angle coming off of the bosses that I could use, (saving myself 2 cuts)
    on both the intakes the measurement is 7" from the bottom of the boss, to the center of the intake. not bad. ( measuring a little over 18" on the #4 intake to the center of the intake joint, on the stock setup)
    it would have been nice to be able to use the same angle on both sides. working with getting past the push rod tubes, and the material that I had on hand, this is what I ended up with, for the moment.

    the main concern I am looking at, is to keep the carb in the center of the intake, and keep the lines looking smooth.
    I am looking at putting a heavier weld on the 2 bottom cuts of the intake joints, and sand the inside down, so it makes a smooth inside radius..
    at the moment I have cut the intakes for the updraft empi carbs. (I keep looking at the setups online, I just cant pull the trigger for one of those set ups yet.
    I keep forgetting that I have a few dual mukini carb sets in hand, and they are side draft. I guess I should look at what I will need for a side draft set up also. and work to that end, also.
    but this little project has got me thinking just a little to say the least. maybe it will work, maybe not.
    the next issue to work on is the exhaust. i have a few things that i have picked up, and about ready to start putting that together.
    I had a few kind of mad at me for a while last summer, when i started it up. with open pipes.
    i kind of forgot I needed to attach a return spring to the throttle, it started up fine, and every time I let off the throttle pull rod, the motor would go instantly wide open. I think i lost some hearing on that one. some friends told me later that they heard it, and they live, about a mile away (in town). needless to say, it didn't grenade on me, yet. it took me a while to figure out why it would go wide open every time I let go off the throttle, sometimes it is the simple things that will get me.
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    Last edited by Bart; 12-24-2016 at 05:03 PM.

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