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Thread: Ram air tested

  1. #1

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    Ram air tested

    Yesterday while drying my ski with a leaf blower I decided to check how effective the ram air mod was. On paper and looking at it it made perfect sense, so without hesitation I did it this past weekend.

    Results- These are my results and not scientific or an end all to the effectiveness of the mod.

    I did the mod as described dremel the front and drilled two holes in the rear as the pictures show. I placed the leaf blower directly in front of the hole and at varying degrees of length from the front opening. What I found is as drawn the ram air mod is worthless. There is no air that comes out the drilled holes in the rear. Air will follow the path of least resistance and with the ram air mod it is out the sliding latch for the hood, around the guages on the very sides of the hood, and out the hole for the actual latch.

    Now, with this in mind I do not think the ram air mod is completely worthless it does grab air and direct it to the rear near the guages, it just does not directly feed into the holes underneath.

    Presently, I think for the mod to become more effective a diffuser needs to be placed in front of the handle bars to redirect the air down there.

    For those of you that have seen an improvement I would be interested in knowing where you position the steering bars because this directly impacts the flow of air out the ram air hood.

    This is just my findings I would really like to know what others find.

    Jason


  2. #2
    Formerly Ultra250 TN Aquaholic6801's Avatar
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    You also have to keep in mind that air is being sucked into those intake holes.

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    Quote Originally Posted by Ultra250 Tn View Post
    You also have to keep in mind that air is being sucked into those intake holes.
    I agree, but it is also sucking air from just in front of the steering. Lot of air shooting out to the steering area, no air coming through drilled holes.

    If this air could be redirected down to the front of the steering I think the mod would become very effective.

    After the ski fest this weekend I will begin experimenting with handle bar positioning and small diffuser flat plates to try and get air going down.

    Jason

  4. #4
    Silence! I Keel You! earthshaker's Avatar
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    Mykull has deflected into his inlets. However the air according to your findings is blowing over this area correct?


  5. #5
    I have found different results. +15 RPM's

    Putting a blower in the hood mod is not accurately testing its benefits.

    Your thinking backwards here. Maybe the name Ram Air is misleading.

    If the engine is consuming the available air from inside the hull you find a vacuum effect. Its this vac that draws in new air from the ventilation tubes. By having the Ram Air mod it equalizes that Vac by having more available air that can be pulled in though the ventilation tubes from the hood verses the rear where the air must past by the hot motor.

    Yes the hood floods with air and does not force air into the front ventilation tubes. It does provide plenty of positive pressure air for the engine intake to draw from. Explained. A hood going 60 MPH will form a vac under it. Rushing air from outside draws the air from under the hood area. This causes a vac along with the engine consuming air. Usually the back ventilators air is positively charged do to your body blocking the sheer. The ram air is forcing air into the hood cavity and allows the engine to pull from an area closer to the intake and not the rear passing the motor.

    This is why water ingestion is not a problem, the water drains out where your finding the air blow out. If it were a true ram then the hull would fill with water during hard riding.

    So we should probably call it the Air Intake Assistance Mod.

    Good testing though, at first I was saying the same thing. Took awhile to test it all out. My Heat Ventilators play a part in the cross draft effect also.


    Man oh man do I sound like a pissy know it all or what.

  6. #6

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    Quote Originally Posted by earthshaker View Post
    Mykull has deflected into his inlets. However the air according to your findings is blowing over this area correct?

    http://greenhulk.net/forums/attachme...1&d=1183767871
    That plate is behind the holes between the steering and hood. If I see it correctly.

    Yeah the air blows over the holes completely. There is a lot of air that comes out, but I could not feel any out of the drilled holes.

    Not scientific at all and not exactly real world, but air and physics do not chanbe much and restriction is a restriction. I would really like for others to do the same thing or just open the hood while riding next time and check how much air really comes out the drilled holes.

    I wish I still had my water injection system because a fine mist of spray in front of the blower would let me see exactly what the air is doing.

    I will come up with something when I have time to experiment.

    Jason

  7. #7
    Beagleman62's Avatar
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    I'll have my hood apart this weekend. For those of you who have already done this, Is there enough room to run hoses, ducts or baffles that would take the air from the inlet on the front to the holes drilled in the back side by the hood latch? Looks like the piece of the black hood backing that sticks up behind the opening in front blocks a lot of air.

  8. #8

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    Quote Originally Posted by Skips313 View Post
    I have found different results. +15 RPM's

    Putting a blower in the hood mod is not accurately testing its benefits.

    Your thinking backwards here. Maybe the name Ram Air is misleading.

    If the engine is consuming the available air from inside the hull you find a vacuum effect. Its this vac that draws in new air from the ventilation tubes. By having the Ram Air mod it equalizes that Vac by having more available air that can be pulled in though the ventilation tubes from the hood verses the rear where the air must past by the hot motor.

    Yes the hood floods with air and does not force air into the front ventilation tubes. It does provide plenty of positive pressure air for the engine intake to draw from. Explained. A hood going 60 MPH will form a vac under it. Rushing air from outside draws the air from under the hood area. This causes a vac along with the engine consuming air. Usually the back ventilators air is positively charged do to your body blocking the sheer. The ram air is forcing air into the hood cavity and allows the engine to pull from an area closer to the intake and not the rear passing the motor.

    This is why water ingestion is not a problem, the water drains out where your finding the air blow out. If it were a true ram then the hull would fill with water during hard riding.

    So we should probably call it the Air Intake Assistance Mod.

    Good testing though, at first I was saying the same thing. Took awhile to test it all out. My Heat Ventilators play a part in the cross draft effect also.


    Man oh man do I sound like a pissy know it all or what.
    Yes, I agree with all you have said, but the air is not coming out where the water will drain. It is actually coming out the latch area and around the sides of the guages.

    When I had the hood apart the water looked like it would drain to the sides or front of the hood.

    Let me say this again, I do not think the mod is completely worthless. I think there is a lot more to be gained by getting the air that is actually coming out the top hooded area. If this air could be redirected down to the steering area it would be lots more air available to the engine.
    Last edited by spaulding; 07-17-2007 at 10:34 AM.

  9. #9
    Silence! I Keel You! earthshaker's Avatar
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    JW, try "canned smoke" I'm pretty sure HD or Lowes carries it. Used for testing smoke detectors. You'll need three peeps to do the test...camera, blower, smoke.

  10. #10

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    Quote Originally Posted by earthshaker View Post
    JW, try "canned smoke" I'm pretty sure HD or Lowes carries it. Used for testing smoke detectors. You'll need three peeps to do the test...camera, blower, smoke.

    Good idea with very large fans feeding the front of the hull.

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