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Does milling the airhorn off really make that big of a differance if one at all? Thanks a lot!

Jeff Given
 

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It smooths out the turbulence caused by the airhorn and adds about 20 cfm or so. At the sacrifice of no choke.

Rick
 

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a Stub Stack accomplishes the same thing and also protects the air bleeds from incoming turbulant air while giving a nice smooth radius for air to follow as it enters the venturis. They really work and without the cost or time of milling off the choke horn and conturing the venturi entrance.
 

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stub stack does a better job of directing air in then not having a choke horn, less turbulence, if that makes sense.
I cut off a choke horn on one of my carbs awhile back, then dremeled it smooth, put it on the car, it was impressive. Then I borrowed a stub stack off a friend and put on a different carb with choke horn, the stub stack won hands down. M.H.O.



<font size=-1>[ This Message was edited by: dark7068 on 1/2/02 1:07pm ]</font>
 

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it fits over the carb so its a better flow of air into carb.



save milling the choke horn, you still keep a choke.
 

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Does anyone know if this substack thing will work on a holley street avenger 670? I may want one.

Thanks
Matt
 

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I have used one on my Dominator since the early 90s and it made a very noticeable difference in part throttle cruising and idling too since it protects the idle and high speed air bleeds from the incoming turbulant air or air from fan or air flowing over the carb when not using an air cleaner.
 

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Cobrajack, it fits inside the aircleaner. It has no effect on raising it, but you need around 1 1/2-2 in. clearance between the stack and top of the aircleaner. If it touches the lid, you have a major restriction, if it's close, your better off without it, worse if you have a drop base air cleaner.
The link above should have info on selection and the space required between the stack and a.c. lid. Just going by memory, and it's shitty at the best of times.

here's a pic of what it would look like installed.




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68 Fairlane/70 Cougar

<font size=-1>[ This Message was edited by: dark7068 on 1/2/02 6:58pm ]</font>
 

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yeah, when you uise a 4 in. filter like that you will. But a 2 or 3 in. might fit without. It says you need 1-1/2 in. clearance. So a 3 in. is fine, most old cars have the room. I have a 3 in. K&N filter on the Fairlane and a 1 in. carb spacer to clear the monte bar, it just touches the hood.
 

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I saw a carburetor flowtest, and on that particular carb, milling the choke horn had no effect on flow.

If the engine was using an air cleaner lid that was close to the top of the carb, milling could open things up quite a bit and allow more flow... But, if the air cleaner lid is plenty far enough from the top of the carb, milling won't do much.

StubStacks... These fit inside the air cleaner, so they don't raise it any. Just be careful that there is PLENTY of room inside. They can do more harm than good if the air cleaner lid is too close to the top of the carb. Short air filter elements and/or drop bases don't mix too well with stubstacks.

By themselves with no air cleaner, stub stacks can be worth quite a bit of power.

Good Luck!

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Mike Burch, 66 mustang real street
302 4-speed 289 heads, 10.63 @ 129.3
http://www.geocities.com/carbedstangs/cmml_mburch.html
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<font size=-1>[ This Message was edited by: n2omike on 1/3/02 4:04am ]</font>
 

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On 2002-01-02 06:16, Cobrajack wrote:
Hey Rick....

Does this thing raise the air cleaner any??? I only have about 1/4" and it will hit the hood!!

Cobrajack

I tried one of these at the track one time without an air cleaner and the stack was so close to the hood that it choked the engine. The car ran slower. That's when I milled my choke horn. That went faster.
I'm not saying the stub stack doesn't work. Just be sure you have hood clearance.
 

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Cobrajack has a 2 in. K&N filter and the funny K&N top, he has 1/4in. clearance between the top and hood, I think it might be benefical in his case. He has room under his cleaner for it, what is your take on it.

Here's a pic of his set-up.



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<font size=-1>[ This Message was edited by: dark7068 on 1/3/02 7:36am ]</font>
 
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