Register now to get rid of these ads!

Technical Convert overhead to a flathead?

Discussion in 'The Hokey Ass Message Board' started by etwheels, Oct 5, 2012.

  1. DD COOPMAN
    Joined: Jul 25, 2009
    Posts: 1,121

    DD COOPMAN
    Member

    I'm listening! DD
     
  2. ______

    This guy is a no show?
     
  3. Isnt that what real flatheads are?:rolleyes:
     
  4. Rusty O'Toole
    Joined: Sep 17, 2006
    Posts: 9,480

    Rusty O'Toole
    Member

    Years ago there was a little story in Hot Rod. One of the writers was a flathead fan back in the fifties. He wanted to buy a used Hilborn injection that was hanging on the wall of a speed shop but had to save up for it. One day he was in the speed shop and the Hilborn was gone. He asked what happened to it. The counterman pointed to a guy disappearing out the door and said "he bought it".

    Quickly he ran out the door and looked around, but there were no old Fords in the parking lot, just a guy under the hood of a 57 Plymouth which was then a year or 2 old.

    He went over and had a look, the guy was bolting the Hilborn on a flathead under the hood of the Plymouth.

    He asked "why would you put a flathead in this car??"

    The guy said "Cause I blew up the Olds motor"

    Now that's a hot rodder.
     
  5. etwheels
    Joined: Jul 8, 2008
    Posts: 39

    etwheels
    Member
    from ca.

    I'll call him and have him send me some pics. I have seen it run and Seen the parts and patterns he used to made it. Dick is a very creative guy and has done many unorthodox things, most have worked. He is still one of the most creativeand outside the box thinkers i know.
    scott
     
  6. RichFox
    Joined: Dec 3, 2006
    Posts: 10,004

    RichFox
    ALLIANCE MEMBER

    Please find out why he did it.
     
  7. etwheels
    Joined: Jul 8, 2008
    Posts: 39

    etwheels
    Member
    from ca.

    Here are the photos of Dicks flathead. HE made patterns to cast the deck, heads and front covers. His son Blaine, an expert machinist, did alot of the design and machining on the patterns for head and deck water passages to get the cooling correct. Dick said he would sell engines or the complete tooling and design package if there was interest.
    scott
     

    Attached Files:

  8. etwheels-- what are we looking at here?
     
  9. 38FLATTIE
    Joined: Oct 26, 2008
    Posts: 4,350

    38FLATTIE
    Member
    from Colorado

    Scott, thanks for posting!

    There is no doubt that Dick and his son have talent! It's pretty spendy, and not really my cup of tea.

    The design, machine work, and overall workmanship is awesome though! I've never seen the 'reverse' of the normal OHV conversion before, so that's pretty cool!
     
  10. RichFox
    Joined: Dec 3, 2006
    Posts: 10,004

    RichFox
    ALLIANCE MEMBER

    Unreal. I would not have believed it with out the picture. Just proves what is possible when you just want to do what you want to do and don't care what anyone else thinks.
     
  11. bobscogin
    Joined: Feb 8, 2007
    Posts: 1,761

    bobscogin
    Member

    Just my opinion, but I would think that on OHV engines the lobe profile is predicated on the rocker arm ratio providing an increase in lift through it's ratio. A flathead gets it's valve lift solely from the cam lobe. The Ford Windsor has a ~1.6 rocker arm ratio, so that cam would only lift a flathead valve 62% as high as it lifts the Windsor valve. For a .500 lift in the Windsor, you'd get .310" on the flathead. Maybe enough to run, but probably wouldn't make much power.

    Bob
     
    Last edited: Oct 9, 2012
  12. rotorwrench
    Joined: Apr 21, 2006
    Posts: 633

    rotorwrench
    Member

    I always figured at some point someone would cast or machine a new complete upper deck & cylinder assembly that, with lots of machining, could be installed in an old flathead block that had excessive cracks or other damages rendereing it unrepairable otherwise.

    I never figured someone would do it to an overhead block. Sound like someone was bored and had a lot of time on there hands. With that much bore, even barely adequate breathing would likely make more power than anything Henry ever invisioned.
     
  13. Ummm, something weird here... You show a page from a website ("back" and "next" buttons) dated 2006, but there is absolutely NOTHING coming up on a search for this swap. The only thing that comes up for "rodmotion" is a low-buck dyno.

    Not saying it didn't happen, but it looks like they are for sale from your pictures...but where?
     
  14. seb fontana
    Joined: Sep 1, 2005
    Posts: 6,891

    seb fontana
    Member
    from ct

    ALL that work and the exhaust ports are still routed to the OUTSIDE of the block? Why not just make them up top? As far as camshaft goes getting enough lift with the Ford .875 dia lifter might be hard, just going to a roller lifter might do it or boring the block out for bigger would be required...For power [hp] I would say one hp per cube would not be unrealistic IF you have the build from scratch option and you have the durability/oiling of the windsor lower end and real durable parts for boosted applications?...
     
  15. RichFox
    Joined: Dec 3, 2006
    Posts: 10,004

    RichFox
    ALLIANCE MEMBER

    There isn't a lot of difference in lobe profiles between flathead and overhead engines, unless you are serious with a flow bench and dyno to know what is really happening. Attached is a picture of my Plymouth bangers. MoPar produced them as flatheads. The first one I built was the OHV engine with the Ford head. I used a reground stock cam. After running it for a few years I built the flathead version. I used the same crank, rods, pistons, and cam from the OHV engine. Worked fine. So that cam went from a flathead to an OHV and back in a flathead. The OHV engine holds the Muroc V4/GR record and the flatmotor set the V4F/FMR record at El Mirage, but no longer holds it. So the cam couldn't have been all that bad.
     

    Attached Files:

  16. I find this to be OUTRAGEOUSLY COOL!

    When did this occur and is the guy still making these? I want one.

    I thought about making valve covers that looked like a flathead for my 302 just to look cool in my 36. Having a real flatty that could produce big time cubic inches on a strong crank would be awesome.

    I still can't figure out how he routed the exhaust?????
     
  17. Ned Ludd
    Joined: May 15, 2009
    Posts: 4,212

    Ned Ludd
    Member

    Very good point. It really does want the Cadillac layout.

    There are tangible advantages to a flathead, i.e. a lightweight valve train, which would allow rpm given enough flow; and serious quench turbulence, which allows quite a bit of scope for a high compression ratio. However, the latter exposes the main disadvantage of a flathead: compression and breathing are at odds with one another. Optimize compression to make good use of that turbulence, and you end up with valves like panel pins. Size valves for half-decent volumetric efficiency and you're stuck with 4:1 CR. All this argues for forced induction, and at a considerable displacement ratio.
     

  18. I am with Rich on this one. Even if the only reason is because I can.

    As lame as it sounds and as much as it goes against my quest for speed I still get kind of giggly when I think about it. I guess some things need to be done just because.
     
  19. Gromit
    Joined: Oct 13, 2011
    Posts: 726

    Gromit
    Member

    It's like watching someone jump a shark tank on a bike. I have no desire to try it, but it's kinda fun to watch.
     
  20. RichFox
    Joined: Dec 3, 2006
    Posts: 10,004

    RichFox
    ALLIANCE MEMBER

    As i remember the really racy flatheads had about .404 lift cams. There are two Ford flatheads that have run over 300 mph on the salt. Anybody know what cam lift they have? I have had some experience with DOHC race engines. Lifter suronds the valve spring and rids on the cam. Pretty low lift compared to rocker arm engines i knew. But faster.
     
  21. Well done - perhaps there are improvements to be made or maybe forced induction will be the answer. But the thing is that he has made a Ford Flathead using a modern Ford block - something half of the experts here told us couldn't be done. The other half told us flatheads aren't worth bothering with because of the low power output potential - on that logic we'd all be pulling our American V8's and fitting japanese turbocharged 4 cylinder engines.
     
  22. 38FLATTIE
    Joined: Oct 26, 2008
    Posts: 4,350

    38FLATTIE
    Member
    from Colorado

    Ron Main wouldn't give me the specs, but said it was over .500.

    Jimmy Stevens ran .480 wth 280 duration, but thought that he should have used his .510 lift cam, which he offered the specs to me for.

    Don't forget Jazzy Nelson, who won a LOT of races with the 505-A.

    I'm using a .525 lift, 270 duration. The new roller cam will be similar, with more exhaust duration.
     
    Last edited: Oct 11, 2012

  23. Rich,
    I think that the thinking on a different cam shaft is that on a flatty it is all lobe lift where as a valve in head gets lobe lift enhanced by the rockers.

    This is not an arguent for either just what I think that everyone is leaning towards. The thing to remember is that on a flatty your lift is limited by the pockets in the heads, if you increase the pocket you loose compression so it may be counter productive to do so.
     
  24. 38FLATTIE
    Joined: Oct 26, 2008
    Posts: 4,350

    38FLATTIE
    Member
    from Colorado

    Beaner, if you use a stock head, increasing the pocket would result in less compression.

    Remember, the flatheads Rich asked about, Ron Main and Jimmy Stevens, are full race flatheads. They had special heads built, to compensate for the lift.

    ...and of course, on those engines, if you need more compression, you just turn up the boost!:D
     
  25. But if you dial up the boost too much it becomes a blivet!!! :D:D:D
     
  26. CutawayAl
    Joined: Aug 3, 2009
    Posts: 2,144

    CutawayAl
    Member
    from MI

    Yes, flatheads do have some pluses. But, when it's all said and done the pros and cons don't stack up well against what has replaced it. That's why they went away.
     
  27. plan9
    Joined: Jun 3, 2003
    Posts: 4,045

    plan9
    Member

    that is a neat setup! giant intake runners, pretty much a straight shot to the valves. well done!!
     
  28. rotorwrench
    Joined: Apr 21, 2006
    Posts: 633

    rotorwrench
    Member

    The exhaust is still a mystery from those photos. I can see what appears to be openings into the valve chamber area. No sign of exhaust ports on the outside in those photos. There isn't enough room to run it between cylinders there for the center siamese exhaust ports.

    More info would be needed to even see if they run the exhaust to the outside of the block. Under the manifold? Maybe there is a reason folks haven't heard much about this conversion yet.
     
  29. mustangsix
    Joined: Mar 7, 2005
    Posts: 1,297

    mustangsix
    Member

    One technical advantage a flattie has is that there is less mass in the valvetrain. It's working very much like an OHC pushing a bucket tappet. Imagine an XK Jaguar cam but with that cam in the block pushing the valves up instead of in the head pushing them down.

    Did anyone ever make a roller cam for a flathead?
     
  30. RichFox
    Joined: Dec 3, 2006
    Posts: 10,004

    RichFox
    ALLIANCE MEMBER

    Anybody running giant lifts on ford flatheads like these is doing it without cam bearings or with bored out bearing holes. Also a giant lift isn't much help unless your port flow will handle it. On my Packard i ran a 505C. But the ports leveled off at about 400 lift. The rest was just to make piston clearance tighter. Ron and Jimmie cut new ports into their flatheads and run compressors to force the air in and out. I think people consider cams to be almost magical. When Dema was talking to me about some cam I got from him, halfway through the talk he said "it's really an old Winfield grind. They all are." I am sure that is not completely true today. But largely true.
     

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2021 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.