Author Topic: Velocity Stack Vs. Scoop  (Read 7197 times)

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Offline TIMINATOR

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Re: Velocity Stack Vs. Scoop
« Reply #40 on: November 22, 2011, 07:55:56 AM »
Carrerra dude, you need to try the boat without the scoop! The aircleaner inside keeps the air from flowing around the rear of the carb, you are only using about half of the aircleaners surface area. Make 1" or so holes on the bottom of the scoop to allow air to feed the backside of the carb. This restriction will richen up the secondaries quite a bit. Not what you want. Put it on a flowbench the way you run it, then remove the elements, you will be amazed.  TIMINATOR

Offline David

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Re: Velocity Stack Vs. Scoop
« Reply #41 on: November 22, 2011, 08:25:45 AM »
Carrerra dude, you need to try the boat without the scoop! The aircleaner inside keeps the air from flowing around the rear of the carb, you are only using about half of the aircleaners surface area. Make 1" or so holes on the bottom of the scoop to allow air to feed the backside of the carb. This restriction will richen up the secondaries quite a bit. Not what you want. Put it on a flowbench the way you run it, then remove the elements, you will be amazed.  TIMINATOR
Hey Tim question for you...
At speed isn't the air being forced into the back of the scoop and feeding that carb?
It would seem to me if you drilled holes in the rear of the scoop you'd be decreasing the pressure by giving it a way out?
I could see your point if this setup was just sitting on a flow bench and not moving...

I know nothing about this stuff so I'm just asking questions...
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Offline 454 blue boat

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Re: Velocity Stack Vs. Scoop
« Reply #42 on: November 22, 2011, 08:50:53 AM »
no David the carb will take air from any were it can get it from .and sometime forcing it in isn't as good as you would think.Its like you remember the the air ram scoop on the camero 69 or so and how the air was sucked in from the back of the scoop in front of the wind shield they say that was the best air intake of all.Dont know if I made since or not but im trying lol

Offline 454 blue boat

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Re: Velocity Stack Vs. Scoop
« Reply #43 on: November 22, 2011, 08:53:50 AM »
Carrerra dude, you need to try the boat without the scoop! The aircleaner inside keeps the air from flowing around the rear of the carb, you are only using about half of the aircleaners surface area. Make 1" or so holes on the bottom of the scoop to allow air to feed the backside of the carb. This restriction will richen up the secondaries quite a bit. Not what you want. Put it on a flowbench the way you run it, then remove the elements, you will be amazed.  TIMINATOR

I was told the same thing on my scoop by Bill to do the same thing inside so that it wouldnt over pressure it

Offline carreradude

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Re: Velocity Stack Vs. Scoop
« Reply #44 on: November 22, 2011, 10:24:16 AM »
Carrerra dude, you need to try the boat without the scoop! The aircleaner inside keeps the air from flowing around the rear of the carb, you are only using about half of the aircleaners surface area. Make 1" or so holes on the bottom of the scoop to allow air to feed the backside of the carb. This restriction will richen up the secondaries quite a bit. Not what you want. Put it on a flowbench the way you run it, then remove the elements, you will be amazed.  TIMINATOR

There is an inch and a half gap between the carb mount plates under the scoop already. If it wasn't there I would have made holes when I set up the motor. Thanks for the tip tho!!

Offline wolfie

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Re: Velocity Stack Vs. Scoop
« Reply #45 on: November 22, 2011, 10:56:33 AM »
Carrerra dude, you need to try the boat without the scoop! The aircleaner inside keeps the air from flowing around the rear of the carb, you are only using about half of the aircleaners surface area. Make 1" or so holes on the bottom of the scoop to allow air to feed the backside of the carb. This restriction will richen up the secondaries quite a bit. Not what you want. Put it on a flowbench the way you run it, then remove the elements, you will be amazed.  TIMINATOR

There is an inch and a half gap between the carb mount plates under the scoop already. If it wasn't there I would have made holes when I set up the motor. Thanks for the tip tho!!

Mike, I'd love to see some detailed pictures of your interior!! I want to set mine up very similar!
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Offline carreradude

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Re: Velocity Stack Vs. Scoop
« Reply #46 on: November 22, 2011, 11:37:15 AM »
Oh crap! I forgot to put up some pics for ya Wolfie. Dang CRS!!!   :41616-4:

Stay tuned...

Offline 78_Tahiti

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Re: Velocity Stack Vs. Scoop
« Reply #47 on: November 22, 2011, 04:05:04 PM »
Scott, the reason the cowl induction works well at speed, is the air flowing over the car (much like an airplane wing) creates a low pressure area of undisturbed air. This smooth air flow flows through the carb, much like pouring water from a full glass into an empty glass. Well as long as the butterflies are open. The uninterrupted air flow creates a lot more stable venturi pulse through the carb & will enhance accurate fuel metering by the carb.
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Offline wolfie

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Re: Velocity Stack Vs. Scoop
« Reply #48 on: November 22, 2011, 04:42:52 PM »
Oh crap! I forgot to put up some pics for ya Wolfie. Dang CRS!!!   :41616-4:

Stay tuned...

Standing by!!!  :biggrin:
"Save the Endangered Tree Octopus! It's as real a threat to our planet as global warming!" http://zapatopi.net/treeoctopus/

Offline 78_Tahiti

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Re: Velocity Stack Vs. Scoop
« Reply #49 on: November 22, 2011, 06:41:27 PM »
Oh crap! I forgot to put up some pics for ya Wolfie. Dang CRS!!!   :41616-4:

Stay tuned...

Standing by!!!  :biggrin:
I think sitting by would prolly be more comfortable Wolfie!  :4_1_72:
If It Floats, F@cks, or Flies, Its Cheaper to RENT IT!

 


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