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  1. ArcticDave

    Legal Eagle Question

    The original Legal Eagle is rated @ 500lb gross. The XL is 575lbs gross. I wouldn't go much over either of those limits without beefier wing spars at least. More than likely some fuselage reinforcing as well. How much does that O-100 weigh?(Nevermind...looked on Pete's website- 105lbs, no...
  2. ArcticDave

    Measuring engine torque

    Thanks for replying...both of you. I have been busy with fuselage stuff lately and put the engine on back burner. I did uncover it yesterday to inspect if it weathered our summer ok. All looks good, so as soon as I can get a test club built, I can resume work on it. Concerning the test club...
  3. ArcticDave

    Measuring engine torque

    Yep! The moment arm is exactly in the center and the rotating shaft is centered with the crankshaft. Instead of putting the scale down there where the spring is(making it harder to read), I used that spring as a calibrated resistance. I applied a known force(fishing scale) to the moment arm...
  4. ArcticDave

    Measuring engine torque

    Yes the engine can pivot freely. I used a 4' moment arm to decrease the amount of force applied to the end. For my little engine I was expecting ~ 60 ft lbs of torque. That should equate to 15 lbs at the moment arm. On a good run up I only saw ~5 lbs of force. The device works...it just reads...
  5. ArcticDave

    Measuring engine torque

    I was hoping somebody was familiar with it. I won't waste much time with it then. I ordered a TinyTach yesterday and I will probably get a non contact model to verify everything. That was something I hadn't even considered! I pulled some wood out of the barn yesterday for test clubs, but it...
  6. ArcticDave

    Measuring engine torque

    I was taught to estimate a 3-4% loss in power for every 1000 feet above MSL. You touched on something important in density altitude. We live within 40 miles of downtown Phoenix AZ, so elevated summer temps are the norm. According to the cheat sheet I have for density altitude, today was a cool...
  7. ArcticDave

    Measuring engine torque

    Mr. Wynne's dyno appears to a similar concept! His is closer to the Whatley stand than mine, but measuring the same thing. Vigilant1, that is a really good idea, referencing the indicator needle to test clubs! I had thought about lighter springs to give the needle more range in order to observe...
  8. ArcticDave

    Measuring engine torque

    Indeed. I agree, one data point is not enough. I have the "wood bar dyno" spreadsheet that was posted on the Eagler's Nest forum. Looking it over, it appears a 34" bar that is 2.27" square should be the right size for testing maximum output. A few shorter bars, with smaller cross...
  9. ArcticDave

    Measuring engine torque

    I think I have to. The engine seems to be producing a little more power than the 40 hp I was anticipating...and the prop is sized for. Before I send this propeller back, I'll try building a wood bar to run on it. Thanks for reminding me of that! I had forgotten it completely.
  10. ArcticDave

    Measuring engine torque

    Well I can confidently say, this doesn't work quite as I intended. Even a 3/4 throttle run with a 55x22 prop... the needle barely budged at 4k rpm, getting nowhere near where it should have been pointing. Good thing I needed a stand anyway and it didn't cost anything extra!
  11. ArcticDave

    Measuring engine torque

    I got the engine running today, but didn't get video of the dyno operating... because I forgot to do it. There was kinda a lot going on. I'll try again for dyno video tomorrow after fixing a valve cover leak and doing something different with that temporary fuel tank.
  12. ArcticDave

    Measuring engine torque

    Forgive the silence, but this has taken longer to do than I expected. Doesn't it always? Anyway...here is the prototype junkyard dyno. I was able to wrangle an unsuspecting victim into helping me mount the engine this morning. Now I still need to mount the throttle and instrument panel, and it...
  13. ArcticDave

    Measuring engine torque

    Thank you! I can't wait to hear it run. I like that distributor cap. I bookmarked that till I can buy it. Thanks I will look into gnumeric since I use Windows! I made good progress today on it. The main assembly is tacked up and waiting on cooler morning temps to finish the welding.
  14. ArcticDave

    Measuring engine torque

    ****** Arise from the dead, old thread of mine! ****** After many setbacks I finally finished my engine... almost two years later! :) I am going to work on this dynometer more today. I started it way back then and didn't complete it. Hopefully I can contribute some useful content to HBA. You...
  15. ArcticDave

    Bob Hoover's HVX VW Engine Mods.

    Thankfully tube buggies are completely legal here in Arizona. They require insurance and all that, but I can drive anywhere in my buggy...and i do. :cool: Back to the subject of HVX mods, Pops... have you ever messed with Mr. Hoover's oil pressure valve modification? I did it to this half...
  16. ArcticDave

    Bob Hoover's HVX VW Engine Mods.

    Looking good! It has the lines of an old Chenoweth. If you're going to run it off road, I would recommend some X bracing in front of the cabin. I did that to mine and it really stiffened the chassis. I can hit something off camber now and the frame doesn't twist at all. See below :) I have a...
  17. ArcticDave

    Bob Hoover's HVX VW Engine Mods.

    SMH...thats genius man.:cool: I've already assembled these rockers, but I will certainly give that a try on the next one. Thank you! An 1835 pushes my tube buggy along just fine!
  18. ArcticDave

    Bob Hoover's HVX VW Engine Mods.

    Dan, I have a question if I may? I did all of the Hoover mods to the engine I'm building now, but I did not groove the rocker bushings. I grooved the shafts and nearly gave myself a fit trying to figure out how to do the rockers. How did you do it? Also,on the last page you were discussing...
  19. ArcticDave

    Measuring engine torque

    As soon as I've got my fuselage ready to paint I'll start building something simple and go from there. I won't have an engine ready until this winter sometime. Just trying to plan ahead and be prepared. Thank you all for throwing out some ideas with me...I appreciate it :-)
  20. ArcticDave

    Measuring engine torque

    Dang....you guys sure give a fellow a lot to think about! The water brake would be very accurate I think, but probably above my pay grade and more expensive than the engine itself. When I was younger and smarter I worked in a shop that rebuilt Detroit diesel engines. We had a dyno that every...
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