300 hp @ 4000 rpm...can it be done?

Discussion in 'Chevy' started by TXFlyGuy, Aug 21, 2012.

Help Support HomeBuiltAirplanes Forum by donating:

  1. Dec 9, 2016 #41

    Armilite

    Armilite

    Armilite

    Well-Known Member

    Joined:
    Sep 6, 2011
    Messages:
    3,022
    Likes Received:
    244
    Location:
    AMES, IA USA
    Your 4.3L= 262.4 Cubic Inches. How Big can it be Bored and Stroked to?

    To make 300hp at Max 4000rpms takes about 383ci to 427ci depending on how radical you want to get, unless you use a Turbo.

    Your 262ci with just a Turbo with 7 lbs of Boost could make around 298hp at 4000rpms. Have a Peak Flow Rate of 448cfm.

    Most Small Blocks make Max HP at 6000rpms. Anything over 9.0cr you would want to burn 100LL.

    Your 262ci built mildly 9.0cr, for 91 Octane, 2.02in 1.60ex, 800cfm carb, 550 lift Cam could make:
    4000/1.71 = 2339.2rpms = 227hp
    5000/1.71 = 2923.9rpms = 294hp
    6000/1.71 = 3508.8rpms = 310hp

    Your 262ci built mildly 10.0cr, 2.02in 1.60ex, 800cfm carb, 550 lift Cam could make:
    4000/1.71 = 2339.2rpms = 236hp
    5000/1.71 = 2923.9rpms = 306hp
    6000/1.71 = 3508.8rpms = 328hp

    Your 262ci built mildly 11.0cr, 2.02in 1.60ex, 800cfm carb, 550 lift Cam could make:
    4000/1.71 = 2339.2rpms = 243hp
    4500/1.71 = 2631.6rpms = 283hp
    5000/1.71 = 2923.9rpms = 317hp
    6000/1.71 = 3508.8rpms = 343hp


    I would think it smarter to use a higher Redrive Ratio to take advantage of your HP. An O-200 is rated 100hp at 2750rpms.
    4000rpms/2750rpms = 1.454545454545455 or 1.5 Ratio
    4500rpms/2750rpms = 1.636363636363636 or 1.6 Ratio
    4750rpms/2750rpms = 1.727272727272727 or 1.7 Ratio
    5000rpms/2750rpms = 1.818181818181818 or 1.8 Ratio
    6000rpms/2750rpms = 2.181818181818182 or 2.2 Ratio
     
    Last edited: Dec 9, 2016
  2. Apr 7, 2017 #42

    TXFlyGuy

    TXFlyGuy

    TXFlyGuy

    Well-Known Member

    Joined:
    Apr 26, 2012
    Messages:
    1,493
    Likes Received:
    436
    Location:
    Republic of Texas
    This entire thread is now a moot point as we have the LS376/480. It will do around 345 hp at 3700 rpm.
    And...it is going to sound awesome!
     
    Chris In Marshfield likes this.
  3. Jun 1, 2019 #43

    RSD

    RSD

    RSD

    Well-Known Member

    Joined:
    May 20, 2019
    Messages:
    207
    Likes Received:
    42
    Continuing this thread rather than starting a new one - if you needed 650hp out of an LS3 at 3800 rpm what would you do to the motor?
     
  4. Jun 1, 2019 #44

    poormansairforce

    poormansairforce

    poormansairforce

    Well-Known Member

    Joined:
    Mar 28, 2017
    Messages:
    649
    Likes Received:
    154
    Location:
    Just an Ohioan
    Turbocharger
     
  5. Jun 1, 2019 #45

    BJC

    BJC

    BJC

    Well-Known Member

    Joined:
    Oct 7, 2013
    Messages:
    9,534
    Likes Received:
    6,308
    Location:
    97FL, Florida, USA
  6. Jun 1, 2019 #46

    Dana LaBounty

    Dana LaBounty

    Dana LaBounty

    Member

    Joined:
    Mar 29, 2019
    Messages:
    16
    Likes Received:
    5
    Ya'll are getting into the realm of power to weight ratios of WWII fighters, bring money. I'm building such a engine currently but it's not for the faint of heart or budget constrained. I'll have 650hp but I'm starting with ALL new parts and machined from the beginning with aircraft use as the intent. Were the LS engines are great in cars I would never put those internals in a aircraft, PERIOD. I started with a Brodix block and Chevy bowtie splayed valve head CASTINGS. I'll have an easy $10k into the top end and valve train. My projection is $65k-$70k for my firewall forward.
    The biggest engineering project is getting the oiling system to work at all attitudes. Straight, level, fast and positive "G" are all easy. If I'm going to have this kind of power and a airframe to match I want to be able to use it ALL.
     
  7. Jun 1, 2019 #47

    RSD

    RSD

    RSD

    Well-Known Member

    Joined:
    May 20, 2019
    Messages:
    207
    Likes Received:
    42
    Just one? and anything else?
     
  8. Jun 1, 2019 #48

    TXFlyGuy

    TXFlyGuy

    TXFlyGuy

    Well-Known Member

    Joined:
    Apr 26, 2012
    Messages:
    1,493
    Likes Received:
    436
    Location:
    Republic of Texas
    Be careful. The last person that custom built a V8 with this much power literally crashed and burned. The rescue people could not get to him, as the aircraft was engulfed in flames. His friends warned him not to fly that engine. He did not listen.

     
    Last edited: Jun 1, 2019
  9. Jun 1, 2019 #49

    poormansairforce

    poormansairforce

    poormansairforce

    Well-Known Member

    Joined:
    Mar 28, 2017
    Messages:
    649
    Likes Received:
    154
    Location:
    Just an Ohioan
    One big one at 20 psi will get you there, don't know for how long. You and D.L. above need to exchange ideas as he is doing it but at what rpm?
     
  10. Jun 1, 2019 #50

    Dana LaBounty

    Dana LaBounty

    Dana LaBounty

    Member

    Joined:
    Mar 29, 2019
    Messages:
    16
    Likes Received:
    5
    Here's the thing, I'm building an aircraft engine, not CONVERTING a engine from a car or truck. It's doable but not cheap. I'm not trying to be cheap. I'm having a billet crank manufactured for reverse rotation so no idlers will be required in the PRSU. I want maximum reliability so there are no shortcuts. If I only needed 300hp I'd get a IO-540 set it up as a AEIO with 10:1 piston and be done with it. Mine will be intercooled, supercharged and dyno tested to optimize the power curve, prop choice and PRSU ratio.
     
  11. Jun 1, 2019 #51

    Dana LaBounty

    Dana LaBounty

    Dana LaBounty

    Member

    Joined:
    Mar 29, 2019
    Messages:
    16
    Likes Received:
    5
    Was engine failure the cause of the crash and if so what failed?
     
  12. Jun 1, 2019 #52

    blane.c

    blane.c

    blane.c

    Well-Known Member HBA Supporter

    Joined:
    Jun 27, 2015
    Messages:
    3,257
    Likes Received:
    557
    Location:
    capital district NY
    Billet crank? For that kind of power? Am I the only one queasy?
     
  13. Jun 1, 2019 #53

    TXFlyGuy

    TXFlyGuy

    TXFlyGuy

    Well-Known Member

    Joined:
    Apr 26, 2012
    Messages:
    1,493
    Likes Received:
    436
    Location:
    Republic of Texas
    As far as I know, it was not a single item that failed. PSRU and/or engine. Terry's friends told him not to fly that engine. It was a special built V8 using components that were of very high quality, not your every day crate motor. The PSRU was American made. 650 hp.

    http://www.kathrynsreport.com/2012/11/kronk-wolffe-p-51-mustang-replica-vh.html
     
    Last edited: Jun 1, 2019
  14. Jun 2, 2019 #54

    Dana LaBounty

    Dana LaBounty

    Dana LaBounty

    Member

    Joined:
    Mar 29, 2019
    Messages:
    16
    Likes Received:
    5
    Queasy? Something you ate? Billet is as strong as you can get, superior to even non-twist forgings.
     
  15. Jun 2, 2019 #55

    Kyle Boatright

    Kyle Boatright

    Kyle Boatright

    Well-Known Member

    Joined:
    Nov 12, 2012
    Messages:
    792
    Likes Received:
    430
    Location:
    Marietta, GA
    Without some details, particularly ones implicating the engine or PSRU...
     
  16. Jun 2, 2019 #56

    Dana LaBounty

    Dana LaBounty

    Dana LaBounty

    Member

    Joined:
    Mar 29, 2019
    Messages:
    16
    Likes Received:
    5
    Too nice today for working on projects. Push the Darmah SS out and ride to Myrtle beach for a snack.
     
  17. Jun 2, 2019 #57

    TXFlyGuy

    TXFlyGuy

    TXFlyGuy

    Well-Known Member

    Joined:
    Apr 26, 2012
    Messages:
    1,493
    Likes Received:
    436
    Location:
    Republic of Texas
    The fatal crash was a direct result of engine/PSRU failure. Terry Kronk crashed into a ravine near the departure airport. He burned to death in the ensuing fire.

    An individual near the crash attempted to assist, but was badly burned and had to cease efforts.
     
  18. Jun 2, 2019 #58

    BJC

    BJC

    BJC

    Well-Known Member

    Joined:
    Oct 7, 2013
    Messages:
    9,534
    Likes Received:
    6,308
    Location:
    97FL, Florida, USA
    The crash was, but the fatality was not related to the engine failure. As dissected in your thread about the deadly engine, the crash was the initiating factor, but the root cause of the fatality was an improper restraint system.


    BJC
     
  19. Jun 2, 2019 #59

    TXFlyGuy

    TXFlyGuy

    TXFlyGuy

    Well-Known Member

    Joined:
    Apr 26, 2012
    Messages:
    1,493
    Likes Received:
    436
    Location:
    Republic of Texas
    Improper restraint system in Kronk’s Mustang? Where did you read that, as it would be helpful to the rest of us. The engine failed, or a combo failure engine/PSRU.
    The post crash fire is what killed Terry, from all accounts. Or, killed instantly from the explosion on impact. Either way, still fatal.

    The owner of Supermarine Spitfire is one of his friends who warned Terry about the power plant. I spoke with the gentlemen, and got the story first hand.

    https://www.pprune.org/archive/index.php/t-499529.html
     
    Last edited: Jun 2, 2019
  20. Jun 2, 2019 #60

    BJC

    BJC

    BJC

    Well-Known Member

    Joined:
    Oct 7, 2013
    Messages:
    9,534
    Likes Received:
    6,308
    Location:
    97FL, Florida, USA
    I was referring to this one https://www.homebuiltairplanes.com/forums/threads/mazda-fatality.26378/

    Thought you were, too.


    BJC
     

Share This Page

arrow_white