Trying to achieve turbonormalizing the home-built way

Discussion in 'Firewall Forward / Props / Fuel system' started by geosnooker2000, Aug 11, 2019.

Help Support HomeBuiltAirplanes Forum by donating:

  1. Aug 11, 2019 #1

    geosnooker2000

    geosnooker2000

    geosnooker2000

    Well-Known Member

    Joined:
    Mar 30, 2019
    Messages:
    100
    Likes Received:
    10
    Location:
    Somerville, TN
    I am struggling with a mechanical theory and was hoping for some expert opinions. If someone's intent was to build a 0-320 and turbonormalize it, there are a couple of very expensive "bolt-on" options. But it seems to me, one of the hallmarks of the experimental aircraft is innovation coupled with simplicity and affordability. To wit, a standard of TN systems is this thing called an Absolute Pressure Controller - one of these things that costs somewhere in the neighborhood of $1300:
    [​IMG]
    They run off of upper deck pressure, and tell the waste-gate what to do by use of oil pressure. The next thing to consider is that aircraft waste-gates are about 4 times the cost of an automotive waste-gate. Like, a hartzell wastegate @ Aircraft Spruce costs $1829. The same thing (roughly) in a car application costs about $200. That's nine times. That's ridiculous.

    I keep trying to understand the fluid dynamics of it, and I just keep coming to the conclusion that you should be able to operate a normalized turbo using manifold pressure (or upper deck pressure) to an automotive waste-gate (air pressure), but my mind is telling me that that would operate the waste-gate in the exact reverse of what I'm looking for. Do I have that right? I feel like someone has already tried to make this work. Please discuss...
     
  2. Aug 12, 2019 #2

    Turd Ferguson

    Turd Ferguson

    Turd Ferguson

    Well-Known Member

    Joined:
    Mar 14, 2008
    Messages:
    4,629
    Likes Received:
    1,595
    Location:
    Upper midwest in a house
    How much boost does a car normally see? 5-6 psi? So that will turbonormalize you to 5-6000 ft?
     
  3. Aug 12, 2019 #3

    pictsidhe

    pictsidhe

    pictsidhe

    Well-Known Member

    Joined:
    Jul 15, 2014
    Messages:
    6,203
    Likes Received:
    1,592
    Location:
    North Carolina
    The mechanically controlled car turbos boost to X psi above atmospheric. There are electronically controlled ones that jolly well do what the ECU tells them to do. The ECU controlled ones are slightly different, their wastegate is controlled by an ECU varied vacuum rather than by boost. I'm sure Ross could sell you a control unit to run a car type at a fraction the cost of the heavier and less reliable aircaft ones.
     
  4. Aug 12, 2019 #4

    TFF

    TFF

    TFF

    Well-Known Member

    Joined:
    Apr 28, 2010
    Messages:
    11,315
    Likes Received:
    3,120
    Location:
    Memphis, TN
    I would first consider a manual wastegate. Just like a mixture control or prop control. Adjust as needed and once familiar you will know how much for ballpark adjustment for takeoffs and then you can trim it. Without a constant speed prop you will have a narrow window of adjustment. I would also consider an auto style wastegate. Just don’t get a Chinese one.
     
  5. Aug 12, 2019 #5

    TFF

    TFF

    TFF

    Well-Known Member

    Joined:
    Apr 28, 2010
    Messages:
    11,315
    Likes Received:
    3,120
    Location:
    Memphis, TN
    Aviation parts have liability insurance for the manufacturer payed up front on their end. That is one reason parts are expensive. Low volume does not help either.
     
    Chilton likes this.
  6. Aug 12, 2019 #6

    geosnooker2000

    geosnooker2000

    geosnooker2000

    Well-Known Member

    Joined:
    Mar 30, 2019
    Messages:
    100
    Likes Received:
    10
    Location:
    Somerville, TN
    This would be in conjunction with a vpp. (Electronic) (airmaster)
     
  7. Aug 12, 2019 #7

    TFF

    TFF

    TFF

    Well-Known Member

    Joined:
    Apr 28, 2010
    Messages:
    11,315
    Likes Received:
    3,120
    Location:
    Memphis, TN
    Fancy hardware
     
  8. Aug 13, 2019 #8

    geosnooker2000

    geosnooker2000

    geosnooker2000

    Well-Known Member

    Joined:
    Mar 30, 2019
    Messages:
    100
    Likes Received:
    10
    Location:
    Somerville, TN
    I don't guess I would mind half as much if there were some non-TSO turbo components. Seems like there would be, but I can't find them.
     
  9. Aug 13, 2019 #9

    rv6ejguy

    rv6ejguy

    rv6ejguy

    Well-Known Member

    Joined:
    Jun 26, 2012
    Messages:
    3,640
    Likes Received:
    2,669
    Location:
    Calgary, Alberta, Canada
    Almost nobody in the progressive homebuilt world uses aviation type WG controllers or wastegates. All the Reno Sport class guys use automotive type stuff.

    Cheapest proven way to control MAP is an automotive dual chamber WG/ actuator coupled to a miniature air regulator. Use the lightest possible WG springs and that determine your minimum boost pressure. As you climb, there will come a point where the MAP starts to fall off at WOT. Crank down the regulator a few notches and you can restore the MAP.

    An absolute controller is nice but, expensive and there isn't much need in a plane that flies mostly below 12,500 or even mid teens.
     
  10. Aug 15, 2019 #10

    geosnooker2000

    geosnooker2000

    geosnooker2000

    Well-Known Member

    Joined:
    Mar 30, 2019
    Messages:
    100
    Likes Received:
    10
    Location:
    Somerville, TN
    My goal is to be able to cruise @ FL17 or 18. (for speed + economy) Finding myself drifting back to the idea of a Subaru EJ25 turbo if I can't put together a TN system for a Ly 0-320 for under $5000. I mean, by the time you buy a relatively good used 0-320 and then add the cost of the turbo system, + who knows what... magneto is gonna fail soon, or the cost of a top overhaul soon, or whatever, I might as well be "throwing a lot of money at a FF package for a Subaru" as someone said in another thread.
     
  11. Aug 15, 2019 #11

    TFF

    TFF

    TFF

    Well-Known Member

    Joined:
    Apr 28, 2010
    Messages:
    11,315
    Likes Received:
    3,120
    Location:
    Memphis, TN
    Most people do not like sucking on O2. My boss will but just about everyone else will fly at 8-10k unless jumping the Rockies. Also you need to look at what the true airspeed is and your VNE. You don’t want to be redline everywhere you go. Vans has that problem with the RV9. Same fuselage as a RV7 with a longer wing. It was made for smaller Lycomings and people started putting constant speed and big engines on it and they cruise around at VNE. Vans engineering is one of the more conservative and believable. When they say don’t I believe them.
     
    Turd Ferguson and rv6ejguy like this.
  12. Aug 15, 2019 #12

    Turd Ferguson

    Turd Ferguson

    Turd Ferguson

    Well-Known Member

    Joined:
    Mar 14, 2008
    Messages:
    4,629
    Likes Received:
    1,595
    Location:
    Upper midwest in a house
    It sounds good on paper but you'll rarely fly at that altitude with any kind of reliability. Several months out of the year you'll find challenging weather in the high teens; you'll need icing protection year round; weather avoidance gear. Nah. Plus, I have never seen an inexpensive turbocharger installation.
     
  13. Aug 15, 2019 #13

    SVSUSteve

    SVSUSteve

    SVSUSteve

    Well-Known Member

    Joined:
    Aug 21, 2007
    Messages:
    3,803
    Likes Received:
    896
    Location:
    Indianapolis, IN
    There’s nothing simple about that, at least if you want to refrain from destroying the engine. It’s not the 1960s anymore. There’s no need to reinvent the wheel because what you seek is available off the shelf. You can have cheap, safe, and performance. But you’re limited to two of those options.
     
    Last edited: Aug 15, 2019
    pictsidhe likes this.
  14. Aug 15, 2019 #14

    SVSUSteve

    SVSUSteve

    SVSUSteve

    Well-Known Member

    Joined:
    Aug 21, 2007
    Messages:
    3,803
    Likes Received:
    896
    Location:
    Indianapolis, IN
    Put a humidifier bottle on the cannula and you’ll never know it’s on (unless you crank it to 4-6 L/min).

    The sad thing is that most people who don’t like in the mountains are low grade hypoxic at 5,000 ft. It contributes to fatigue and may explain some of the more Whiskey Tango Foxtrot accidents.
     
    geosnooker2000 likes this.
  15. Aug 15, 2019 #15

    geosnooker2000

    geosnooker2000

    geosnooker2000

    Well-Known Member

    Joined:
    Mar 30, 2019
    Messages:
    100
    Likes Received:
    10
    Location:
    Somerville, TN
    Thank you for saying that. It's true, and to be quite honest, I plan on having oxygen available at all times on my plane. Reason being, my family and I live @ 400 MSL. We drove up Pikes Peak Highway (14,xxx feet) in 2006 the day after driving to Colorado Springs in one day. When we got only half way up, my daughter passed out from just walking a few yards to take a picture. By the time we got up to the top, we could barely walk around. Got to the inside structure there on top and all 5 of us just laid our heads on the table. I almost lost all my vision just getting from the truck to the door of the place.

    So yes, I am a big advocate of supplemental o2 at any altitude.

    Additionally, I appreciate all of the opinions about whether or not this is a good idea, or if I would actually use it, and at what percentage of the time. But none of those address the question at hand. If you have something to add about the mechanics of the situation, please do so. But please refrain from trying to define my mission. Just because you wouldn't go to the trouble to "re-invent the wheel" doesn't mean someone else wouldn't derive immense joy from it. If you have a mechanically relevant comment, and want to add words of caution, that's cool. But don't just come in to nay-say. I get all of that I need from my wife.
     
    Last edited: Aug 15, 2019
    SVSUSteve likes this.
  16. Aug 15, 2019 #16

    SVSUSteve

    SVSUSteve

    SVSUSteve

    Well-Known Member

    Joined:
    Aug 21, 2007
    Messages:
    3,803
    Likes Received:
    896
    Location:
    Indianapolis, IN
    I’m a flat lander. My pulse ox was 93-95% for a few weeks back when I did a temp staffing assignment as a respiratory therapist in Wyoming (AKA “America’s Siberia: Where the Men are Men and the Sheep Always Look Anxious” ). That sucked.

    I think a lot of folks give O2 a bad rep because they were originally exposed to unhumidified O2. That’s bloody unpleasant. If you crank the flowmeter all the way to the stops (15 L/min; don’t go over six liters with humidification and much over two without), it honestly would be a good way to extract a confession from someone without leaving external marks.
     
    litespeed and geosnooker2000 like this.
  17. Aug 15, 2019 #17

    Toobuilder

    Toobuilder

    Toobuilder

    Well-Known Member

    Joined:
    Jan 20, 2010
    Messages:
    4,310
    Likes Received:
    3,087
    Location:
    Mojave, Ca
    Not trying to define your mission here, but are you sure you NEED to be normalized? After all, Dave Anders and his wife fly all over the country in their NA RV-4 at 17k. Granted, it's a hot rodded angle valve in a tiny airplane, but he does get some very impressive MPG numbers. SDS ignition and EFI also help.
     
    rv6ejguy likes this.
  18. Aug 15, 2019 #18

    geosnooker2000

    geosnooker2000

    geosnooker2000

    Well-Known Member

    Joined:
    Mar 30, 2019
    Messages:
    100
    Likes Received:
    10
    Location:
    Somerville, TN
    Can you elaborate? I don't know who Dave Anders is, or what a hot rodded angle valve means. I'm going to assume right off the bat that refers to some type of auto conversion? For reference purposes, my airframe is CH640-ish which is a 4 place low-wing. Does Dave run a VPP?
     
  19. Aug 15, 2019 #19

    rv6ejguy

    rv6ejguy

    rv6ejguy

    Well-Known Member

    Joined:
    Jun 26, 2012
    Messages:
    3,640
    Likes Received:
    2,669
    Location:
    Calgary, Alberta, Canada
    Dave Anders is a pretty famous guy who has about the fastest RV-4 around. Modded Lycoming with high CR pistons, EI and EFI.
     
    Last edited: Aug 15, 2019
  20. Aug 15, 2019 #20

    geosnooker2000

    geosnooker2000

    geosnooker2000

    Well-Known Member

    Joined:
    Mar 30, 2019
    Messages:
    100
    Likes Received:
    10
    Location:
    Somerville, TN
    Variable Pitch Prop? And did you supply the EFI? and is it the 0-360?
     

Share This Page

arrow_white