Engines: Cost and weight per HP

Discussion in 'Firewall Forward / Props / Fuel system' started by Vigilant1, Jul 29, 2018.

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  1. Jul 31, 2018 #41

    BJC

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    I don’t understand your reply to my post. Please tell me, in one sentance, your response to my post. Thanks,


    BJC
     
  2. Jul 31, 2018 #42

    TFF

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    It's going to be a William Faulkner sentence.
     
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  3. Jul 31, 2018 #43

    Little Scrapper

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    Haha, that's brilliant!
     
  4. Jul 31, 2018 #44

    Vigilant1

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    Yep, I always look forward to the Kitplanes "Engine Roundup" issues every year, very informative. I don't have my most recent one at hand, but I don't recall a "$/HP" or "Lbs/HP" column in their listings. That's where I was going with this thread: Are there "bargains" in the "$/HP" area (yes, particularly at the low end) and what does it cost us in weight. There's no way this little "thought exercise" could be a comprehensive listing of available engines for homebuilders--Kitplanes already does that better than anyone I know of.
    Okay, I give. I added a 100HP Corvair to the chart (see post 29). But there's no way that an engine with a case and heads that have been run for thousands of hours is "new." :) Still, the Corvairs are interesting and you can buy 'em ready to run. As far as the few "metrics" we are looking at ($/HP, lbs per HP) they are pretty much in line with the other entries in the 80-100 HP range.
     
  5. Jul 31, 2018 #45

    Vigilant1

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    Also, I can find lots of listings for the B&S 810cc in the vertical shaft model, but the horizontal shaft version seems hard to find.

    If we could find a simple, light way to turn the output 90 degrees to drive a prop or two . . .
     
  6. Jul 31, 2018 #46

    BBerson

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    No horizontal version, as far as I know. Shouldn't be that hard to convert to horizontal. Might need an oil pickup and 90° adapter for the carb.
     
  7. Jul 31, 2018 #47

    Pops

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    How about adding this to the list. $9400, 170 lbs, 85 HP, 80 hp continuous HP.
    I thought about this engine for the JMR, but since I had a Cont -C-85, I use what I had. Believe it would make a good engine for the 650 lb EW-- 1050 lb GW airplane. Seems like a good buy to me.

    http://revmasteraviation.com/
     
  8. Jul 31, 2018 #48

    Armilite

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    Lycoming Engines IO-360-L2A
    ENPL Number NRT10437
    New List Price: $83,264
    Core Value: $17,400
    Exchange List Price: $65,864
    Discount Amount: $11,555
    You Pay: $54,309
    Payment: $630.29/Mo.
    + Add to Cart

    Rebuilt

    List Price: $56,722
    Core Value: $17,400
    Exchange List Price: $39,322
    Discount Amount: $6,778
    You Pay: $32,544
    Payment: $377.70/Mo.
    + Add to Cart
     
  9. Jul 31, 2018 #49

    mcrae0104

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    Please share a link for this source. Are those certificated or experimental prices? It's not really fair to compare certificated prices to experimental alternative engines.

    BTW, if anybody at Lycoming is reading this, your website is among the most opaque this side of North Korea.
     
  10. Jul 31, 2018 #50

    pictsidhe

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    There is no horizontal model. Rotate the world 90 degrees and you're all set.
    Alternatively, change the oil pickup and either the carb or the manifold. Considering that the carbs should be rejetted over 3000ft, swappping it for CVs seems wisest.
     
  11. Jul 31, 2018 #51

    pictsidhe

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    What about the various Subarii? I wonder who on here might know all about those?
     
  12. Jul 31, 2018 #52

    BJC

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    No E-AB builder would do that. Check here for reasonable prices. https://www.aerosportpower.com/our-engines/


    BJC
     
  13. Jul 31, 2018 #53

    Vigilant1

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    According to Subaru, they are no longer making small industrial engines. Subaru and the related Robin engines were reportedly very nice, it seems logical that someone has bought the rights to make them, somewhere.

    I'm sure there are many manufacturers of 25-35HP small engines for small ATVs, hydraulic pumps, generators, etc. The OEMs likely don't pay a huge price for each one, but they buy hundreds of them. In our position, the trick is to find a way to buy a single one without paying for 4 levels of markups, and being able to get parts later.
     
    Last edited: Jul 31, 2018
  14. Jul 31, 2018 #54

    Vigilant1

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    +1. And among distributors, finding a price online is as likely as finding nuclear missile launch codes.
    All-up weight data? Notoriously incomplete ("Oh, that weight doesn't include a starter. Or carb. Or pistons.")
     
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  15. Jul 31, 2018 #55

    Vigilant1

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    Some updates, now includes a Corvair (100 HP) and another VW (2331cc)

    Numbers:


    Engine.................HP.......Cost ($)....Weight (lbs)...$ per HP.....Lb per HP
    Lycoming O-360.........180......27,500.(1)...305.............153.........1.69
    Continental O-200A.....100......23,500.......205.............235.........2.05
    Rotax 912 ULS/S........100......19,437.......125.............194.........1.25
    Aeromomentum AM13......100......10,495.(2)...201..(3)........105.........2.01
    Corvair (100HP)...(4)..100......10,500.......219.............105........ 2.19
    VW 2331cc (5)...........85(80)...9,400.......170.............111.........2.00
    VW 2180cc.(6)...........76.......7,175.......167..............94.........2.20
    VW 1835cc (7)...........60.......6,025.......165.............100. .......2.75
    VW 1835cc "basic",(8)...60.......4,750.......145..............80........ 2.30
    1/2VW 37HP "basic"(8)...37.......3,650........85..............99........ 2.00
    Briggs & Stratton 810cc.30.........830........87.(9)..........28.........2.90
    ^^ "" + hub&bearing (8).30.........980........94.(9)..........33.........3.13
    Harbor Freight670cc.....22.........730........97.(9)..........33.........4.41
    ^^ "" + hub&bearing (8).22.........880.......104.(9)..........40.........4.73

    Notes
    (1) Price through Van's direct purchase program. May be higher elsewhere?
    (2) Price is for the Aeromomentum AM13 "low profile" version. The upright version is $8495 = 84.95 $/HP
    (3) Weight is for the AM13 engine, radiator, and coolant
    (4) Azalea Aviation "Spyder." 120HP also available ($12,900)
    (5) Revmaster "R2300". 85 HP max, 80HP continuous
    (6) From Hummel engine site, includes dual ignition system, starter, alternator, carb, Force One bearing and prop hub
    (7) As above, but simple shrink fit prop hub (no Force One bearing and hub)
    (8) Hummel engine site: Shrink-fit hub, single ignition, hand propped, no alternator, with carb
    (9) Includes factory flywheel (which includes factory stator/generator and ignition trigger, etc)

    (10) Estimated price and weight of additional bearing and prop hub: $150, 7 lbs.
     
    Last edited: Jul 31, 2018
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  16. Jul 31, 2018 #56

    Vigilant1

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    The specs page is a little confusing. In various places it says:

    85 HP at 3350 RPM (we'd probably need a prop of very low pitch if we want to see 3350 RPM on takeoff)
    85 HP at 3200 RPM
    82 HP at 2950 RPM continuous
    80 HP at 3000 RPM continuous

    So, something's not quite right with the info on that page.
    Per their spec sheet, the Revmaster has a 94mm bore and 84mm stroke, 8.0:1 CR

    Hummel (Scott Cassler) sells a "2400cc" engine: (85 HP max, 94mm bore x 86mm stroke, unspecified CR). It looks like the weight is 167 (incl carb?) and the price with dual ignition, alternator, starter, Force One hub, and Zenith carb would come to $7,475. That would be $88/HP, which is quite good for a pre-assembled engine in this HP range. It would be interesting to see what heads he uses and to compare them to the Revmaster 049 heads. Keeping the CHTs reasonable will be the challenge.
    Hummel specs (very brief)
    Hummel prices
    One advantage (IMO) of the Hummel/Cassler engines is the use of the Zenith carb and "stock" parts (alternator, ignition) that are available from several sources. But, the Revmaster engines and their proprietary parts are well respected, no doubt.
     
    Last edited: Jul 31, 2018
  17. Jul 31, 2018 #57

    davidb

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    Revmaster claims to have larger cooling fins so maybe their max continuous hp is greater and realistic?
     
  18. Jul 31, 2018 #58

    Vigilant1

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    That's certainly plausible. But what is implausible is the HP remaining flat from 3200 to 3350, or the max continuous HP decreasing by 2 HP with a 50 RPM increase. It >could< happen, but it would take a torque curve that is very erratic. It is more likely that there are some typos on the Revmaster specs page.
     
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  19. Jul 31, 2018 #59

    Pops

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    Has to be typos.
    I wish Scott at Hummel would redo his website, its need a lot of help.

    Three things I don't like about the Revmaster engine, first- is the slide carb, no fuel bowl, no use. I would put a Zenith carb on it, so there is $400 extra cost. Second- I don't like having to take the valve cover pan off and then two oil tight covers to get to the bottom spark plugs. Three- not able to hand prop.

    I do like Scott's 2180 cc engine, but I don't know what he is using for dual ignition, there again, I want to be able to hand prop. Not that much infro on his website. I know Scott, and would trust him at his word and he sells a good product. That means a lot to me.
     
  20. Jul 31, 2018 #60

    mcrae0104

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    Titan seems to be the only one to provide a price you can get to without filling out a quote form. An X360 will run $27k+ according to their spec sheet (option prices, such as FI, are not listed) Powering Your Plane lists these prices for comparison (published 2016):

    • Superior IO-360-B1AC2: $25,600
    • Vans Lycoming XIO-360-M1B: $28,700
    • Titan IOX-360-A4H1N: $28,900
    • Thunderbolt YIO-360-M1B: $32,300

    At any rate, an IO-360 for an experimental plane should not be $83,000 (wherever that number came from)!!!
     
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