Reply With QuoteTalk to Jordy... he is our resident Velocity stack expert.
I was talkin with 4speednup in the PM's and he mentioned getting a velocity stack... then I was like... shit, I got one of those! I took it off and replaced it with some little grill type thing to keep water from goin down the carb when it gets rough. Always was super paranoid about that for some reason. But now that I'm bringing it up here where the lakes arnt very big and dont get much wind kinda got me thinkin about putting it back on (if I can find it in the garage with no bottom). What exactly is the pupose of the thing? ONly thing I could think of is relating to the flow of fluid mechanics and it would increase the velocity of the air going into the engine. Sure more air getting pushed in really fast might help with combustion... but exactly how much of a hp gain can it really produce? Is it even worth putting back on?
Talk to Jordy... he is our resident Velocity stack expert.
I used to have a Mr. Gasket one on my 1979 Bahner 18' and hated it. It had some kind of foam crap inbetween the wire mesh and when the engine would backfire it would catch the foam on fire. It seemed that air passing over the top would create a vacuum and lessen air flow. On my current boat i'm using a velosity stack made by K&N. It draws air through a horizontal filter and seems to work great. They are Coast Guard approved and trap the flames if a backfire occurs.
They're supposed to increase the velocity of the air going into the engine much the same as when a river channel narrows. The equal equal volume of water has to move faster to get through the narrower space. They have never been proven to add horsepower and I doubt you would notice a difference. I did have one on my Southwind though.
wheres jordy?
Someone talkin bout me?I just wanted one cuz they look cool. There are a bunch on ebay, I'd take the foam out before using it. The K+N is the only one I've seen to actually raise HP (Chevy hipo did a dyno test)
With my luck, a 12 yr old girl on a PWC will roost me and send about 5 gallons of water down the carb.:yuk:
I had one and the motor would not idle for shit.
Theorectically, a velocity stack works off of Burnuli's airflow principle. " A column of air moving through a restiction increases in velocity and drops in pressure" The theory is that the reduced air pressure (slightly less than atmospheric pressure of 14.7:1) would allow the engine to pull in more air, thus allowing a slightly richer mixture and making more power. Does it work? Well, I don't know. Maybe if you had an ultra well tuned engine and were working for that last 2 hp, but on our average warmed over ski boats and such, I seriously doubt it. Hope that helps!
No advantages ?
Their Cool.in a retro way
http://www.***boat.com/image_center/.../43CMI-med.jpg
Why do SS boats run them
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