aeromomentum suzuki based engine

Discussion in 'GEO / Suzuki' started by don january, Jun 26, 2016.

Help Support HomeBuiltAirplanes Forum by donating:

  1. Aug 3, 2018 #61

    rv6ejguy

    rv6ejguy

    rv6ejguy

    Well-Known Member

    Joined:
    Jun 26, 2012
    Messages:
    3,749
    Likes Received:
    2,788
    Location:
    Calgary, Alberta, Canada
    Decent price. The earlier port injected engines had some issues. The later GDI engines have a pretty good rep. The engine shown is an earlier port injected version. I think these shared a lot of design features with the Mitsu turbo fours and even some parts are apparently interchangeable.

    You still need engine management, gearbox, proper turbo, rads, intercooler, accessories, exhaust, engine mount. Lots to do past the basic engine.
     
  2. Aug 20, 2018 #62

    aeromomentum

    aeromomentum

    aeromomentum

    Active Member

    Joined:
    Jan 28, 2014
    Messages:
    33
    Likes Received:
    45
    Location:
    Stuart, FL USA
    Sorry for not being active on this thread or forum. As we use the Microsquirt it is fault tolerant and falls back from closed loop to speed/density and then to Alpha/N. There is no limp mode or engine protection. You always get all of the possible power. We have simulated sensor failure. Of course closed loop the fuel economy is better. Actually open loop the power is a little better since we error slightly on the rich side. While we use a wide band for our tuning we use a narrow band for actual use. The narrow band O2 sensors seem to last about 100 hours with 100LL and cost just $35.

    While we start with a new GDI engine for the AM20T we convert it to port injection due to the valve deposit issues of GDI in higher RPM/power usage. Also so far no one I know of has a redundant high pressure fuel pump for GDI and these seem to be not all that reliable at this time.

    While I like the MicroSquirt system I am talking with other EFI providers.
     
  3. Aug 20, 2018 #63

    rv6ejguy

    rv6ejguy

    rv6ejguy

    Well-Known Member

    Joined:
    Jun 26, 2012
    Messages:
    3,749
    Likes Received:
    2,788
    Location:
    Calgary, Alberta, Canada
    Seems like you have the best of both worlds- latest engine combined with more reliable and easier to service and trouble shoot port injection. GDI engines as a whole, seem to all have the carboned up valve issues unless they combine port and DI like Lexus does which is very complex. There is just more to go wrong with all the high pressure hardware- pumps, injectors mounted in the hot chambers etc.- for minimal gains in an aviation application.
     
    Vigilant1 likes this.
  4. Aug 20, 2018 #64

    Vigilant1

    Vigilant1

    Vigilant1

    Well-Known Member Lifetime Supporter

    Joined:
    Jan 24, 2011
    Messages:
    4,044
    Likes Received:
    1,792
    Location:
    US
    I'd put the lack of variable valve timing on these Suzuki engines into the same category--glad to be without it in this application. Just needless complexity we can do very well without.
     
  5. Aug 20, 2018 #65

    rv6ejguy

    rv6ejguy

    rv6ejguy

    Well-Known Member

    Joined:
    Jun 26, 2012
    Messages:
    3,749
    Likes Received:
    2,788
    Location:
    Calgary, Alberta, Canada
    Agreed. While things like VVT and DI show tangible gains in automotive applications, they will show minimal gains in a steady state, high power application like we have in aviation for the most part. I generally recommend people go for earlier non-VVT engines when doing an auto conversion, ditto on the DI versions.

    The Honda powered, Titan T-51 guys see almost power zero change when switching the VTEC on at a given point in the 4500-5000 rpm range. Auto conversion guys are rarely winding engines right out to power peak rpm.
     
  6. Oct 1, 2018 #66

    sotaro

    sotaro

    sotaro

    Well-Known Member

    Joined:
    Feb 27, 2011
    Messages:
    121
    Likes Received:
    16
    Location:
    San Francisco
    While I see the drawbacks to Direct Injection (DI), do you not appreciate the 12-14 compression ratios on gasoline engines? Does the high power lead to spark retard for some reason? I think the current compression ratios (and therefore expansion ratios) are amazing. Or is it that the drawbacks of the high pressure pump, injectors, etc outweigh the improvement in efficiency?
     
  7. Oct 1, 2018 #67

    rv6ejguy

    rv6ejguy

    rv6ejguy

    Well-Known Member

    Joined:
    Jun 26, 2012
    Messages:
    3,749
    Likes Received:
    2,788
    Location:
    Calgary, Alberta, Canada
    Direct injection simply hasn't proven to be as reliable as port injection in the long term. Almost all the OEMs had and often still have issues with the intake valves carboning up severely over time and the very high pressure pumps on some brands aren't lasting well. You also can have the problem of even making these engines run out of the car chassis due to sensor tie-ins with the ECUs. Not many aftermarket ECU solutions for DI engines. Yes, you'd be retarding timing at these CRs at WOT and SL conditions but the cruise efficiency is very good at lower MAP because of these high CRs. Always advantages and disadvantages to almost anything in engine design.
     
    wsimpso1 and ScaleBirdsScott like this.
  8. Jun 6, 2019 #68

    PTAirco

    PTAirco

    PTAirco

    Well-Known Member

    Joined:
    Sep 21, 2003
    Messages:
    3,477
    Likes Received:
    1,000
    Location:
    Corona CA

    A blip-switch will fix that.
     
    bmcj likes this.
  9. Jun 6, 2019 #69

    wsimpso1

    wsimpso1

    wsimpso1

    Super Moderator Staff Member

    Joined:
    Oct 19, 2003
    Messages:
    5,879
    Likes Received:
    3,101
    Location:
    Saline Michigan
    Good to hear from you!

    Make it sound like a Le Rhone. Braap...Braap... LOL. That would sure get people's attention on the ramp.

    I would worry over greatly increasing the time down in the resonance range which should be about mid way between cranking rpm and idle.

    Billski
     
  10. Jun 6, 2019 #70

    aeromomentum

    aeromomentum

    aeromomentum

    Active Member

    Joined:
    Jan 28, 2014
    Messages:
    33
    Likes Received:
    45
    Location:
    Stuart, FL USA
    Keep in mind that at 1800 engine RPM the prop is at just 695 RPM. Lycoming recommends 1000 to 1200 RPM for ground operations but you can pull it back to about 800 prop RPM momentarily. So a geared engine should have lower residual (idle) thrust than a direct drive.
     
    Vigilant1, Heliano and wsimpso1 like this.
  11. Jun 6, 2019 #71

    rv7charlie

    rv7charlie

    rv7charlie

    Well-Known Member

    Joined:
    Nov 17, 2014
    Messages:
    435
    Likes Received:
    170
    Location:
    Jackson
    A Lyc with a fixed pitch prop on a fast plane like an RV with idle set at 800 changes it from a short field to a long field a/c. They *really* don't want to land. One advantage of a good electronic ignition/injection is setting idle (prop rpm) down around 600 or less.
     
  12. Jun 7, 2019 #72

    Heliano

    Heliano

    Heliano

    Well-Known Member

    Joined:
    Dec 24, 2015
    Messages:
    57
    Likes Received:
    30
    Location:
    Campinas, SP, Brazil
    Greetings from the far away south. Allow me to make one comment: Viking (Jan Eggenfeeller) also uses hi RPM idle. In addition to that they have cut the BMW rubber coupler in three parts, as can be seen in their videos, probably to get rid of some resonant mode. But as Mark noted, it is high ENGINE RPM, not high PROPELLER RPM.
     
    Vigilant1 likes this.
  13. Jun 8, 2019 #73

    KeithO

    KeithO

    KeithO

    Well-Known Member

    Joined:
    Nov 30, 2009
    Messages:
    263
    Likes Received:
    31
    Location:
    Jackson, MI
    I have personally met the folks from Megasquirt. Very experienced electronics engineers who retired from Motorola... They built a small production run of peak and hold injector driver boards for me at a very competitive price and lead time. So consider the fact that it is entirely possible to have a custom product made if you have any misgivings about a standard offering. They will handle any part of the process that you need them to and are flexible in you taking over the manufacturing of boards etc and provide all the design files for the work that they do for you. They are located in rural VA so not an unpleasant place to meet up with them face to face....

     
    Vigilant1 likes this.

Share This Page

arrow_white