1/2 VW power output??

Discussion in 'The light stuff area' started by ryanjames170, Sep 24, 2018.

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  1. Sep 24, 2018 #1

    ryanjames170

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    has anyone ever verified the power output of the 1/2 VW engine at all i was thinking on weather or not a 800CC engine could make 30HP or not in a twin.
     
  2. Sep 24, 2018 #2

    Pops

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  3. Sep 24, 2018 #3

    ryanjames170

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    What kind of static thrust do they get out of one anyhow? With "30 hp"
     
  4. Sep 24, 2018 #4

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    Depends on the prop.
     
  5. Sep 24, 2018 #5

    TFF

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  6. Sep 24, 2018 #6

    radfordc

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    Not a lot! I built a 35 hp 1/2 VW for my old Airbike. Here are some comparisons to the Airbike with a Rotax 447 engine.

    447 takeoff roll about 200 ft; 1/2 VW takeoff roll about 400-500 ft.

    447 rate of climb about 700-800 fpm; 1/2 VW rate of climb about 300-350 fpm

    The difference in performance is due to the relatively small prop that the 1/2 VW turns in comparison to what a 447 can turn with gear reduction. A small prop produces less static thrust than a large prop.
     
  7. Sep 25, 2018 #7

    N8053H

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    If you go with a different crank one with longer throws you can squeeze a little more out of these little 1/2 vw's. I believe Scott said mine was 1000cc. It had the bigger jugs, pistons and crank. It also ran great. Pulled a 650 lbs airplane around great at 3100 rpm on climb out.
     
  8. Sep 25, 2018 #8

    addicted2climbing

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    Was yours built from the cut case or full? Any idea what the FWF install weight was? What was your impression on this motor?
     
  9. Sep 25, 2018 #9

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    Friend of mine put a thousand hours on a 37 hp, 1/2 VW in a Mini-Max with no problems. Decided to do a MOH. Him and an old WW-2 fighter pilot flying another Mini-Max did a formation routine at airshows for several years with the 2 MM's.
     
  10. Sep 26, 2018 #10

    Dana

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    Mosler claimed 40HP for their 1083cc CB40 engine (a half VW with a custom case and crank) I had in my Fisher 404 biplane, but most said it was less, maybe 37HP. I got 300-350fpm on a good day, but the plane was designed for the 50HP Rotax 503.

     
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  11. Sep 26, 2018 #11

    addicted2climbing

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    Wow that is surprising and the Mosler has a higher CC than the Cassler modified engines. I really want to use the 1/2 VW on the skylite, but seems the more I read its a marginal option. However the Legal Eagle at our club seems to do pretty good. What was the empty weight of your fisher 404? What was the weight with you in it and full fuel? The more I go back and forth the more the Polini Thor 250 looks good. Also there are a bunch of 250CC 4 stroke PG motors but they are all set up as tractor only. Or at least the ones I have found are.
     
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  12. Sep 26, 2018 #12

    Dana

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    330 empty and 540 gross if I recall correctly. Its performance was far from breathtaking but I had a lot of fun with it. What made the half VW worthwhile was the sound it made (no 2-stroke whine, which is just wrong on a biplane) and the 2GPH fuel consumption, less than half of what the 503 would burn.
     
  13. Sep 26, 2018 #13

    N8053H

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    A friend has a Mosler on an N3 pup. This engine has some compression. Hand propping that engine is a BEAR. My buddy has not put but a few hours on it and we are hoping it loosens up some or gets easier to hand prop. But I do not see this happening. The Cassler 1/2 vw is a cut case. I did like that engine, she ran great. The airplane she was in with a pilot and full tank of fuel tipped the scales right at 600 lbs. This was with a 190 lbs pilot. Gross was 650 lbs. When I purchased her she weighed 650. I put her on a diet.
     
  14. Sep 26, 2018 #14

    TFF

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    Some of that biplane drag was for sure part of the slow climb. The LE really jumps in the air.
     
  15. Sep 26, 2018 #15

    N8053H

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    LE weighs a LOT less.
     
  16. Sep 26, 2018 #16

    ryanjames170

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    Very true 330lbs vs 244 for 30-40hp dose add upto quite a difference.

    Beginning to think though a few V twins can be made to work too, have to leave the airplane world and go to the tractor go cart racing world to find the info..
     
  17. Sep 26, 2018 #17

    Dana

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    I never had any problem hand propping the Mosler.
     
  18. Sep 26, 2018 #18

    N8053H

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    Dana its not that it is a problem, it starts right up, but man it has some compression. So much the prop flexes when you try to start it. I should make a video.
     

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