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Technical Ford Flathead Dizzy

Discussion in 'Traditional Hot Rods' started by redoxide, May 29, 2020.

  1. redoxide
    Joined: Jul 7, 2002
    Posts: 522

    redoxide
    Member
    from Scotland

    Just adding the finishing touches to my current 30 coupe build.

    The car is running a 53 8BA Its was a good running engine when it came out of the donor car a few years ago.

    During the down time the 94 carb gummed up and on first attempt to fire up a few backfires put an end to the powervalve and the carb would run rich..

    I bit the bullet and bought a new 97 but this added the next issue , The vacuum port for the Ford Dizzy .

    As I understand it the carb and dizzy on the 8ba were matched and the dizzy took a ported vacuum from the carb..

    Probably getting ahead of myself I invested in a Bubbas Chevy dizzy converted for the 8BA.

    Bubbas product was spot on but with that dizzy set in the engine and timed Im not so sure the motor is running as sweet as it had been with the Ford Dizzy , even running with the vacuum disconected .

    I Have zero performance parts on the engine, its 99 % stock with the exception of the new single 97.

    Ive got to wondering if the Dizzy from Bubbas is to much for the stock motor. Its not a car that will be hammered often if at all, but it will be driven distances and see regular use .

    With the fixed advance on the Bubbas dizzy will this have an adverse effect on the normal running of the engine ?

    If I were to refit the Ford dizzy would it be appropriate to take the vacuum from the inlet manifold pretty much as most more modern sources are taken from ?

    I just got the impression from running the motor with the original dizzy and the bubbas dizzy that the motor runs sweeter at idle than it does with the bubbas and also revs cleaner and smoother .

    Im pretty sure there is a wealth of knowledge on here covering all angles :)

    My buddy has suggested that I retro fit the new dizzy with a vacuum advance mechanism .. kinda defeats the purpose .

    Im really just seeking advice from anyone who has experience of both dizzys and what tips or tricks they had up there sleeve to get the best from the old motor .

    Fitting the 97 initially transformed it ,

    I might add that I also swapped the plugs , it was running NGKs and I fitted champions , Ive read anecdotes that say Champions are crap.. and the flatty runs better on NGKs , Can brands make a significant difference ?

    looking forward to digesting your replies .
     
  2. 19Fordy
    Joined: May 17, 2003
    Posts: 6,815

    19Fordy
    Member

    Is your coil compatible with Bubba's distributor?
    Post your question on Fordbarn.
    Bubba may even chime in along with many others.
     
  3. v8flat44
    Joined: Nov 13, 2017
    Posts: 446

    v8flat44

    Ole Ron, Charlie NY & Bubba are a wealth of knowlege on the Barn.
    You'll git er fixed & no you can not hook original dizzy to intake. It would run oposite of design intent.
     
  4. tubman
    Joined: May 16, 2007
    Posts: 4,998

    tubman
    ALLIANCE MEMBER

    It could just be that you will never get a stock engine with a 97 and a Bubba's converted mechanical only distributor to run as well as one with a properly functioning stock Loadamatic system. The latter is an integrated complete design, while the former is really just a hodge-podge of parts. This is not knocking a Bubba distributor, but you have to realize that they are intended to run on modified engines (multiple carburetors, hot cams, etc.). While many people knock the original Ford Loadamatic system, when functioning properly on a stock engine, they are top shelf. I ran one for years with no problems at all, and it was a sweet running setup.

    If you want to get your engine running better, adding a vacuum advance is probably a good start. If it were me, I'd go back to stock and put the carb and distributor on the shelf until I could obtain a set of them neat finned heads, a dual manifold, and another 97.

    Oh yeah. Send your 94 to "Charlie NY" for a rebuild; you won't regret it.
     
    Last edited: May 29, 2020
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  5. redoxide
    Joined: Jul 7, 2002
    Posts: 522

    redoxide
    Member
    from Scotland

    coil came with the dizzy. Its the way Bubbas sell them to avoid incompatibility issues.
     
  6. jimmy six
    Joined: Mar 21, 2006
    Posts: 6,403

    jimmy six
    Member

    What’s a dizzy? I thought merry-go-rounds in city parks were outlawed...
     
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  7. Fortunateson
    Joined: Apr 30, 2012
    Posts: 3,129

    Fortunateson
    Member

    I think it is a derivative of a Deusy....
     
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  8. redoxide
    Joined: Jul 7, 2002
    Posts: 522

    redoxide
    Member
    from Scotland

    The coil came with the dizzy. Its the way Bubbas sell them to avoid incompatibility issues.

    I have rebuild kits for the 94 and not adverse to rebuilding one of the many 94s I seem to have accumulated from various sources . Just thought I was doing the right thing with the 97.

    The 97 and the ladamatic actually run prety well without the Vacuum connected . obviously not as well as it might, but better than it does now .

    The 97 and the chevy dizzy start on the button and despite small graduations in timing it really doesnt want to rev cleanly , Its not popping and backfiring, its just hesitant as though it was down on a plug and not firing on all cylinders ..

    For elimination purposes, I will rebuild the 94 and revert to the ported vacuum and see how it runs then .. just in case Im imagining the poor running.

    Regards Heads There seems to be some schools that consider the ali heads to be dress ups and for a steert flatead the cast iron heads are actually pretty decent , Sure a cam and an extra carb will wake things up a touch, but to be honest this is a seriously low budget build .. the carb and dizzy were probably the biggest extravagance.

    Was just looking for that elusive answer that would solve the issues in one hit .. :)

    Will do a bit more research on the loadamatic set up ..
     
  9. tubman
    Joined: May 16, 2007
    Posts: 4,998

    tubman
    ALLIANCE MEMBER

    As to heads; with enough work, stock heads can be made to perform as well as aftermarket heads (certain specialized heads excepted). Aluminum heads have two advantages : They look better to some and aluminum is easier to work with than cast iron when modifying combustion chambers.
     
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  10. 51504bat
    Joined: May 22, 2010
    Posts: 1,849

    51504bat
    ALLIANCE MEMBER

    I guess I'm just lucky. I'm running a Bubba mechanical only on a basically stock 8ba and a 94 rebuilt by CharlieNY. The 8ba was rebuilt with EAB heads and a stock Merc cam. Runs like a top with no issues. Not a hot rod but a good old beater daily driver '39 p/u.
     
  11. alchemy
    Joined: Sep 27, 2002
    Posts: 15,527

    alchemy
    ALLIANCE MEMBER

    Check your wires and plugs.
     
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  12. Garpo
    Joined: Jul 16, 2016
    Posts: 183

    Garpo

    Barney Navarro and others wrote about Ford's use of vacuum advance. On light throttle, which is most of the time on street use, the motor needs about 4 degrees more advance to run clean, which is what the original Ford distributors do. When the throttle is opened the advance drops back to suit. Any centrifugal only set up will work well for straight acceleration but will not be truly smooth at part throttle. This take a lot of reading and experimenting to get your head around.
    When using a non stock distributor, the vacuum port location has to be correct for that unit. The 8BA carb has a special port that links two internal vacuum sources. Some distributors require a vacuum source adjacent to, but above the throttle butterfly, and early Ford used manifold vacuum.
    The key is to understand what is going on.
    Also, if the motor is essentially stock, with Ford heads. Carb and ignition set up correctly, it will run fine with Champion H10s, or just about any brand that has a direct equivalent. There are NO bad brands, just bad mechanics. The plug is usually the symptom, not the cause.
     
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  13. redoxide
    Joined: Jul 7, 2002
    Posts: 522

    redoxide
    Member
    from Scotland

    I have read that in numerous tech items regarding the ali heads being mainly a dress up.. Fortunately I like the just pulled look on the old flathead in my coupe. When I fix the percieved engine running issue, I will be more than happy with the old boat anchor as a power source ..

    DSCF7317.JPG DSCF7210.JPG
     
  14. tubman
    Joined: May 16, 2007
    Posts: 4,998

    tubman
    ALLIANCE MEMBER

    I think you missed my point. I now have a rebuilt '51 Merc in my car, stock Merc cam, a 2GC, reworked Edmunds heads, and a centrifugal only Mallory. It runs just fine and I have no complaints about it. As a matter of fact, I love it because of the increased performance. That being said, just sitting there and idling and for every day puttering around, it's just not as smooth as the stock engine I had in it previously. (It could also just be the load exhaust.)
     
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  15. redoxide
    Joined: Jul 7, 2002
    Posts: 522

    redoxide
    Member
    from Scotland

    There are very definately bad brands and agreed ,bad mechanics .

    Bubbas Distributor ( or dizzy for short, for the education of a few) doesnt have Vacuum so im not worried about the vacuum ports, Im familiar with those and the quirks of the 94 and the loadamatic "dizzy".
    Being a pedantic son of a bitch Im forced by nature to respond to the comment re "the plug being the symptom not the cause " as a competent mechanic you will know thats not 100% accurate , If I have a duff plug its going to cause a misfire .. symptoms that will provide clues, elimination of the source will define the cause . So, a bad plug will cause a misfire .

    Im not a tunner, and not really familiar with the messing around with ballance weights inside dizzys . I understand the centrafugal force throws the weights out creating an advance or retardation of the distributor base plate and subsequent spark timing, but the rest of the science im ignorant of.. Im old school, if it runs its good if it runs bad theres a problem that needs fixing :) apologies for my response appears defensive , Its a character flaw .. cant help myself :)
     
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  16. redoxide
    Joined: Jul 7, 2002
    Posts: 522

    redoxide
    Member
    from Scotland

    I think i am experiencing the same as you, there is nothing actually wrong with the running of the engine, its just not as smooth as it was .. perhaps Im expecting the moon on a stick .. but just seems no matter how well the timing is set , the motor just seems a little "off" and I wondered if that could be tweaked without reverting to the original Ford parts ..
     
  17. tubman
    Joined: May 16, 2007
    Posts: 4,998

    tubman
    ALLIANCE MEMBER

    I think you're right if you sense that "it seems a little off" rather than just "different". Have you taken a compression test? The stock system may have been more forgiving to a low cylinder. How about a vacuum gauge test (I could post one of those charts for the millionth time, but I don't think it's necessary). You've changed both carburetion and ignition, so you should probably start troubleshooting from scratch. One thing we should know; where did the 97 come from? "Clive" in England? a friend? a quality rebuild from someone like "Uncle Max", or maybe even one of the dreaded "Nine Super Seven"'s from Speedway?
     
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  18. Petejoe
    Joined: Nov 27, 2002
    Posts: 10,469

    Petejoe
    ALLIANCE MEMBER
    from Zoar, Ohio

    I’ve been running a stock distributor on my 37 with an 8ba with two 94’s for 20 yrs now.
    I removed one of the two springs on the advance. The Venturi vacuum is split running to both carbs. It runs perfectly.
    Years ago I tried one of Bubbas distributors without an advance.
    I wasn’t happy with it. Like you, it didn’t have the zip I had experienced with the stock unit.
    What new 97 are you using?
    The speedway units had bad reviews for a good while.
    Not putting bubbas gm distributors down. I know alot of people were very happy with them.
    If you do decide to go back to original.
    Be sure to install a new vacuum diaphragm on the old unit. They rot and leak.
     
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  19. tubman
    Joined: May 16, 2007
    Posts: 4,998

    tubman
    ALLIANCE MEMBER

    "Petejoe" - Just to be clear. Do you mean the Bubba's distributor was mechanical advance only (no vacuum) or no advance at all? I wouldn't think he would make a distributor with no advance at all (except for a straight racing application).
     
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  20. jimmy six
    Joined: Mar 21, 2006
    Posts: 6,403

    jimmy six
    Member

    Oh I get it... Dizzy is like “Nil”..The baseball score after 2 innings was “3-Nil” and everyone was playing their positions “spot on”.
     
  21. Petejoe
    Joined: Nov 27, 2002
    Posts: 10,469

    Petejoe
    ALLIANCE MEMBER
    from Zoar, Ohio

    Its been many years since I've tried that distributor.
    So I may be wrong but, I don't remember it having a vacuum source for advance at all.
    I returned it to Bubba. What a great vendor he is.
     
  22. tubman
    Joined: May 16, 2007
    Posts: 4,998

    tubman
    ALLIANCE MEMBER

    Yeah, I know Bubba likes mechanical only distributors better than Vacuum over mechanical. That's probably what you had. There may have been something wrong with it (bad advance curve or a frozen advance). I find your solution to dual carbs with a "Loadamatic" to be quite interesting. I have never tried it (I am a Mallory "flattop" guy myself) but I have heard this before, and don't see any reason it wouldn't work. To be clear, you ran vacuum lines from both carburetors into a "tee" than then on to the Ford distributor?
     
    Last edited: May 30, 2020
  23. redoxide
    Joined: Jul 7, 2002
    Posts: 522

    redoxide
    Member
    from Scotland

    Carb is a new 97 from Clive, a quality product. :)

    And as you ( @ Petejoe) mentioned re the loadamatic unit, I did replace the diaphram in thea unit as there was a previous issue of minor overheating with the engine at load and towing . several avenues were chased and it was nailed down to the vacuum diaphram on the dizzy. With that changed for a new one the engine was fine . symptom and cause again..

    I let the engine sit for a couple of years waiting for the right project , with the bits collected, this engine was selected as the motive power it fitted with the basic look and feel of the build .

    Initially it fired up after its period under the bench , and idled OK but wouldn't rev and banged and popped though the carb and run real rich..
    I traced that to a ruptured power valve.. I weighed up the pros and cons and decided to bite the bullet and buy a NEW 97 from Clive for reliability and having read reviews on Bubbas Ignition, decided that shifting out the loadamatic might be the right decision too.

    I started with fitting the carb, that made a hell of a difference. The motor run great, idled sweet and revved clean and free. The loadamatic was still installed but with no vacuum connected.

    Having schooled myself on the 94/ ladamatic set up I decided that the mechanical advance ignition set up might be the answer.
    Fitted the new unit, fired it up first time and idled fine but it wasnt happy to rev as claen as it had done. Small tweeks on the timing didnt improve matters .. Decided that it might be an idea to change the plugs , a service item that was on the cards .. Installed the champions and to my mind it run even worse , not that it run bad, but just didnt sound right ..

    I got to thinking that perhaps the Bubbas ignition was a full on hard driving style of ignition designed for WOT driving .. Thats not the case though. They are supposed to be good across the range .

    Im going to make a few adjustments and see if things can be improved , but its been reassuring to read that at least one other person has had the same feeling regards the feel of there engine with the alternative ignition set up.

    Its also enlightening to read that by simesing the vacuum source from twin 94s that the loadamatic can run fine, seems that a lot of the time they are simply replaced for 97s .

    Im just keen to draw from other folks experiences, you never know I might just be overlooking something really obvious .

    Im going to rebuild the 94 , I have kits and need to rebuild for another engine, so will revert to full Ford set up and see if its just my imagination .. will also do the compression test, and even revert to NGKs just to eliminate any variables

    Thanks again for the clues and personal experiences with similar set ups..



    .
     
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  24. alchemy
    Joined: Sep 27, 2002
    Posts: 15,527

    alchemy
    ALLIANCE MEMBER

    Do your adjustments and replacements one at a time and report the results. That way we can see which part made an improvement.
     
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  25. leon bee
    Joined: Mar 15, 2017
    Posts: 483

    leon bee
    Member
    from Arkansas!

    An interesting discussion, please keep us posted.
     
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  26. redoxide
    Joined: Jul 7, 2002
    Posts: 522

    redoxide
    Member
    from Scotland

    Will do.. I borrowed my buddies all signing all dancing electronic timing light earlier today, can eyeball everything in one display .. hes going to drop off his Vacuum gauge so we can assess the vacuum at certain revs and degrees of advance .. I have a wee bit of homework to do to fully understand what Im trying to achieve ..
     
  27. tubman
    Joined: May 16, 2007
    Posts: 4,998

    tubman
    ALLIANCE MEMBER

    Seeing as how you said that the engine had set for a couple of years, you should try to borrow his compression tester as well. Some rings may have gotten stuck during the ensuing period, which can really foul things up.
     
  28. Petejoe
    Joined: Nov 27, 2002
    Posts: 10,469

    Petejoe
    ALLIANCE MEMBER
    from Zoar, Ohio

    Yes one vac line from the distributor to a tee then two lines to each carb.
     
  29. redoxide
    Joined: Jul 7, 2002
    Posts: 522

    redoxide
    Member
    from Scotland

    OK doke

    Had a look over the old boiler today, made a few checks and tests, not complete yet but here are some results .

    These tests were with engine cold , air cleaner off, full throttle, and full cycle cranking.

    Bubbas ignition fitted and static timed on the pin at TDC ( which I believe is actually set 2deg advanced )

    Proper Blue coil as supplied with Bubbas kit.

    Champion RH10c plugs.


    So Compressions: All pretty decent and in cylinder number order . ( in PSI )
    1 = 122
    2= 122
    3=122
    4=122

    so at this point im thinking thisis all going to well, best prepare for the let down.

    5 = 125
    6=122
    7=122
    8=125

    At this point nobody could have been more surprised than me ..

    with the compression's looking decent I went forward and checked the ignition

    Checked the plugs and gapped to 25 thou.
    Plus were out the box just the other day . 2 from each bank appeared to be on the lean side and similarly 2 from each side were displaying rich .. ( I forgot to note which cylinders were lean and which were rich , kicked myself for that )

    Set up the electronic timing light and marked the dimple on the crank pulley with some white correction fluid ..

    fired the motor up and it idled sweetly at a steady 600 rpm I could take it down to 450 and it was still happy but it sounded sweet at 600.

    dialed in 2 degrees advance to the timing light and checked the marks, Timing was spot on . but this is also where it gets fruity .

    Reference from Bubbas noted that the timing was on the pin at idle and 11 degrees ignition / 22 engine at 2500rpm

    This is where it goes bad . The engine was idling sweet and sitting happy . bringing the revs up slowly and adjusting the timing light to show degrees of advance I was up to 27 degrees of advance at 2300rpm and the motor was running like crap.. wasn't banging and popping but it wasnt smooth, when I took it to 2500 it was dog rough .. with timing way off the recommended normal ..

    Will check for vacuum leaks and fetch my buddies vacuum gauge to see if there is anything causing the poor running , why it should be advancing to 27 degrees and beyond is another issue ..

    Im all ears .. Im no flathead expert .. Always wanted to run a flathead, always crapped out and run something more modern.. took 30 years to bite the bullet .. :)
     
  30. tubman
    Joined: May 16, 2007
    Posts: 4,998

    tubman
    ALLIANCE MEMBER

    Compression looks excellent. It sounds like the advance is not working correctly. Perhaps Bubba can find some time to look it over. I think spring and weight kits as well as advance limiting bushings are available for these, so you may want to dig into it yourself. Could also be worn bushings, but the fact that it just came from Bubba would belie that. It is possible though; I know from personal experience.
     

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