1. After 20+ years it's time to pass the torch. If you are interested in acquiring this forum please contact support@cv-performance.com for details. Any spam will be reported and blocked.
  2. Welcome to Bike Talk, a forum for all bikers and motorcycle enthusiasts. If you are new to Bike Talk, be sure to register for free and join the conversation.

    There's always someone around willing to help out with questions or give a friendly wave back. All Harley and metric riders are welcome.

creating air flow tip

Discussion in 'Motorcycle Tech Talk' started by voodoo1, May 19, 2004.

  1. voodoo1

    voodoo1 New Member

    Joined:
    Mar 31, 2004
    Messages:
    525
    Likes Received:
    0
    Location:
    Ohio
    My buddy was involved in machining the heads and airflow tricks to help HD regain a 1000cc class land speed record a few years ago. One of the rules is the bike must "appear stock." after much dyno-ing and tricks, they knew that when the throttle was hit hard sprays out of the cv carb and sucked back in on the pistons' stoke. they said it looks like a tornado with what they were dealing with. My friend better known as "the professor" Machined a cone and grooved it with spirals to help create a stronger vortex into the carb. It mounts with the stock air cleaner and centered on the carb(small tip towards the carb) they gained 6-7 hp!! on their runs. So now my 02 wide glide will be the test case for him to try and basically create a serious vortex. Grant it the bike they set the record is little different so they put it on his STOCK 98 sporty and got the results!!! He stated the throttle response is improved greatly.
    We like to go for the stock look(sleeper) and still maintain the reliability for trips. Anyone interested in the results of for my 88cc? I'll try to get the final deminsions. This guy is in the wrong line of work but those that know him are lucky enough to gain from his machinist technoknow itall knowledge
    Last edited: May 19, 2004
  2. CD

    CD Guest

    Velocity...

    Voodoo1,

    These are more commonly known as velocity stacks. We used them on our small block MOPARS when the cam overlap got WAY big. When you start running a large lift, high overlap camshaft, drag pipes and open air cleaners reversion gets really bad a lot of times.

    There are other forms of these velocity stacks that are shorter and act to direct and straighten airflow into the venturi inside an aircleaner.

    Regardless of their design, the intent is to increase velocity and straighten airflow.

    I am not sure that I have ever come across a design like his but can see the possibilities. I did know of one that was stepped so that reversion pulses could not back up as easily but it was a very large 8-10" on top of a big Dominator Holley.

    That is the beauty of hot rodding, the process never ends and there are always the new ideas around the corner.

    Speed may cost a lot to go fast but sometimes you can go faster just on an idea.
  3. voodoo1

    voodoo1 New Member

    Joined:
    Mar 31, 2004
    Messages:
    525
    Likes Received:
    0
    Location:
    Ohio
    yeah I get it but this is just too cool that it was an internally hidden system. We use an 850 and mess with a tunnel ram every now and then on the small block chevy we run. the piece on this bike is actually held in towards the carb with the mounting screws behind the stock air cleaner cover. seen stacks would this be considered an inverted stack :D ? or a inverted vortexed air thing-uh-muh-jiggy? either way if I get a pic of it, I'll try and figure out how to upload it on here for you to see.
    Gotta love the power of the mind to come up with some creative and simple ideas for MORE POWER!!! :cool:

Share This Page