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  1. #1

    Impeller pitch and engine afr?

    Will a impeller pitch change the afr because of more load for the engine? example i am tuning with a 13/18 but ordered a skat 15.5/22.5 for my turbo will this change my afr?


  2. #2
    My name is Sean and I am addicted to STXs smokeysevin's Avatar
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    within reason it will, it puts the motor in a different load region of the map, if its a standalone you can adjust for it, most factory maps don't make much of a difference, I went from a 10/16 to a 12/21 and it made a huge difference but that is a big difference in pitch.

    Sean

  3. #3
    i am tuning my ski so i am better just waiting for the 15.5/22.5 and do the tune, no point in tuning 2 times.

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    My name is Sean and I am addicted to STXs smokeysevin's Avatar
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    Under load the engine will require more fuel, I would only tune with the big prop if I were doing it, the reason I went through the 2 props in mine is that my engine is right in between the power output of the 2 kawi motors and I didn't have a baseline. What are you using to tune?

    Sean

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    shrabber's Avatar
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    that 13/18 use it for a wind chime. I would start off pitching it to a 15/24 to 15/25 ( what boost you running ?) you do not want to start tunning afr's until you get a somewhat control of your rpm's and Of course you do Not want to bang the Limiter Lean either

  6. #6
    i am usind v-tech data logger with the new to be release map edit function.just ordered the new 15.5/22.5 i guess i gotta wait since that is the impeller i will be using it just makes sense to tune with that one.

  7. #7
    Quote Originally Posted by shrabber View Post
    that 13/18 use it for a wind chime. I would start off pitching it to a 15/24 to 15/25 ( what boost you running ?) you do not want to start tunning afr's until you get a somewhat control of your rpm's and Of course you do Not want to bang the Limiter Lean either
    only looking to push 15-18psi boost nothing crazy.

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    shrabber's Avatar
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    What are you using is that a skat track 3 blade? with that boost I think you should be in the Ball park maybe a tweak here or there. Good luck buddy. How did your turbo turn out?

  9. #9
    Quote Originally Posted by shrabber View Post
    What are you using is that a skat track 3 blade? with that boost I think you should be in the Ball park maybe a tweak here or there. Good luck buddy. How did your turbo turn out?
    i am using a 13/18 for the moment but gotta wait 4-5 days for a custom skat blade then another week b4 i can get it here. turbo turned out ok just need to remove fuel from a 80s map i got. since v-tech docent have any turbo map for 1000's i am ok till about 7000 rpm and 8lb boost then it is pig rich at 9ish or 10 afr there after will keep testing.

  10. #10
    Quote Originally Posted by shrabber View Post
    What are you using is that a skat track 3 blade? with that boost I think you should be in the Ball park maybe a tweak here or there. Good luck buddy. How did your turbo turn out?
    when running a turbo do you start with a base of 43.5psi of fuel with a 1:1 ratio or do we set it at 60 psi and no 1:1?

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