L-head power improvement

Discussion in 'Flat Fender Tech' started by neptco19, Nov 14, 2005.

  1. Nov 14, 2005
    neptco19

    neptco19 That guy.... Sponsor

    Athens, GA
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    Me and my buddy where trying figure out how to get some more power out of the L-head when the time comes to rebuild it. Is it possible to deck the block and cut new valve seats to improve compression. Looked at the thought of decking the head but that would seem to reduce the flow through the valves due to the way its shaped. Any body have any experience doing this?


    And no a :v6: is not a option. Your welcome Billy :beer:
     
  2. Nov 14, 2005
    blevisay

    blevisay Oh Noooooooooooooooo! Staff Member Sponsor

    Portland Tn.
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    There is a performance head if you can find one..........and one guy over at the G was working on a dual carb set up
     
  3. Nov 14, 2005
    neptco19

    neptco19 That guy.... Sponsor

    Athens, GA
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    after some searching I found the head your talking about billy
    [​IMG]
    http://clubs.hemmings.com/clubsites/wocv/willywilly/willywilly.htm

    Reading the site about the head dosnt seem like it raises the compression that much, from 6.5:1 to 7:1. Is that much of a gain worth trying to hunt one of these heads down if it would even be possible.

    and looking at this intake
    [​IMG]
    http://clubs.hemmings.com/clubsites/wocv/willywilly/willywilly.htm


    it appears that the intake could be made fairly easily. Any idea on if it would be possible to set the linkage up so that one of the carbs would work like a secondary? so it would kick in at full throttle :twisted:
     
  4. Nov 14, 2005
    48cj2a

    48cj2a http://bantamt3c.com Sponsor

    Central Illinois
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    Hardened Valve seats and new valves would be a good idea to run unleaded pump gas.
     
  5. Nov 14, 2005
    blevisay

    blevisay Oh Noooooooooooooooo! Staff Member Sponsor

    Portland Tn.
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    There was one on e bay not long ago
     
  6. Nov 14, 2005
    blevisay

    blevisay Oh Noooooooooooooooo! Staff Member Sponsor

    Portland Tn.
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  7. Nov 14, 2005
    runnamuck

    runnamuck look out!

    hickory, nc
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    yeah, we are diffinently going hardened valve seats and valves. probaly cam and a little stiffer springs. i know these and f-head have head gasket issues, but with the advances in gasket technology i think we could go 8 or 9 to 1 if we can deck the block enough without compromising the water jacket stenghen.
     
  8. Nov 14, 2005
    jd7

    jd7 Sponsor Sponsor

    Nacogdoches,Texas
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    don't think these engines can take that much compression. remember reading about it somewhere. I thought about doing the same thing.
     
  9. Nov 14, 2005
    mb82

    mb82 I feel great! Sponsor

    Charlottesville Va
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    Jason I bet with some ingenuity you could make the second carb be progressive.
     
  10. Nov 14, 2005
    Mcruff

    Mcruff Earlycj5 Machinist Sponsor

    Albertville, AL
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    You can't make the carb progressive unless you make a plenum to run on top of this intake tube, the way this is setup is the one carb feeds 2 cylinders and the other carb feeds the other 2 cylinders. I would love to see a hopped up L-head. If it were me, 3 angle valve job with hardened seats, swirl polish the valves, electronic distributor. Polished chambers in the flat head, mill head surface to gain compression but don't go overboard. Dual carbs and the intake along with a K&N filter and larger flow air tube. Header and good free flow muffler and 2" pipe along with getting rid of the factory generator and using an electric fan to gain all the power out of the motor you can.
     
  11. Nov 14, 2005
    w3srl

    w3srl Curmudgeon-in-training Staff Member Sponsor

    Pittsburgh, PA
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    The problem with progressive carbs on a log-type manifold is that the only time all 4 cylinders get an even amount of fuel is at WOT, because of where the carbs have to be mounted. (One carb is always closer to two cylinders than the other carb.) This is why dual-quad setups are almost always have the secondaries progressive to the primaries ON THE SAME CARB, as opposed to having one carb be progressive to the other. A tri-power setup however, almost always has the center carb running the show until you floor it, and then all three carbs go WOT. Most don't even have idle circuits in the outboard carbs!

    Now, you could go waaay overkill and put 3x1bbls with a progressive linkage on an L-head, or go 2x1 with a non-progressive setup.

    As for getting more power out of a L-head, I think I'd look really hard at a belt-driven supercharger set up in a "blow-through" configuration. Limit your boost to a few poundsand you'll have a right snappy little Jeep with gobs of torque on the bottom end where you need it, as opposed to a turbo motor that never really wakes up until 3-4000 RPMs.
     
  12. Nov 14, 2005
    CJMace

    CJMace Member

    Columbus, OH
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    Im sure this has been talked about, but Clifford makes a great header for the L-head. Great improvement in performance. They also sell the weber 2bbl carb conversion, I dont know much about that, its real expensive, and dont think it could possibly make that much difference. my engine was rebuilt by the PO and he says that the head has been milled about .009 or so. Dont know about the benefits of that one either, but Ive had it off, and there is not much clearance at all. For a while I was running an electric fan, and I never could get it just right, but while it was off....my little squirrels ran faster than they ever had before. That little engine revved up jsut fine, even with bigger heavier tires. I put a pertronix ignition in, and it starts great, and idles much smoother, but Im not sure there was any spectacular increase in HP. As far as being able to handle the extra compression, I think they are capable of some increases, for high altitude running, but not too much. Thats about all Im familiar with.

    Im sure you guys have heard this before, but the ol History Channel told me that Willys Overland got the contract with the US military because they were the only ones developing more than 60HP, and they also had to be able to withstand 4,000 RPM for at least 40 consecutive hours. Thats pretty crazy, but it makes me feel a little better about planting the right foot in the mud. Good luck with the buildup, and let us know what you find, especially about a source for that head!!
     
  13. Nov 15, 2005
    53Flattie

    53Flattie Intigator

    Easley, SC
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    Yes - that is CRAZY!!!!!!!!!

    Pretty darn durable motor.
     
  14. Nov 15, 2005
    BlueFlu

    BlueFlu past owner of some ecj5's

    Hermitage, TN
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    You could always swap in a F head. :D
    The dual carb setup looks promising.
     
  15. Nov 15, 2005
    timgr

    timgr Jeepin' Nerd Sponsor

    Medford Mass USA
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    AFAIK an F-head will fit if you use a side-draft carb. How about a couple of side-draft motorcycle carbs (Mikuni)?

    Also I would point out that the 4000 rpm torture test was on a new engine, and maybe under no load. Not dissing the 134, but running 4000 rpm today would be risky and pointless.
     
  16. Nov 15, 2005
    BlueFlu

    BlueFlu past owner of some ecj5's

    Hermitage, TN
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    That would look SWEET!!
     
  17. Nov 15, 2005
    timgr

    timgr Jeepin' Nerd Sponsor

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    Hmmm.. maybe with the L-head ... IIRC the F-head intake manifold is cast in to the head and the port faces up, so mods would be hard.
     
  18. Nov 15, 2005
    BlueFlu

    BlueFlu past owner of some ecj5's

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    With a sheet metal intake anything is possible. :D
     
  19. Nov 15, 2005
    mb82

    mb82 I feel great! Sponsor

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    How about individual throttle bodies with EFI, if you want to dream why not dream big.
     
  20. Nov 15, 2005
    timgr

    timgr Jeepin' Nerd Sponsor

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    Usually when you think performance, you consider the 4 Cs: cam, carburetion, compression, cubic inches. You should be able to get a few more hp out of the L-head without any radical changes - make it breath better, raise the CR, and possibly a bumpier cam (custom grind?).

    There's no easy way to increase the displacement, but you can increase the effective displacement by packing more air and fuel into the available space. This would play to some of the 134's strengths - strong, thick cylinder walls, and steel crank & rods. Could work out pretty well as long as your boost comes on at a low enough speed and you don't try to spin too fast.

    BTW Dick Datson has a few pages in his Jeep performance book about porting the flathead (I think it's in reference to the 226, but should apply to the 134) - probably there's info in books about hot rodding the Ford flathead V8 too.
     

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