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Is swan-neck Weber Manifold as bad as Vizard says?

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ncbugeye

ncbugeye

Jedi Warrior
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I have this Weber manifold, see attachment.

Our good friend David Vizard is very scathing about swan-neck manifolds in his excellent encylopedia on A-series tuning. Does anyone have any actual experience that confirms Vizard's assessment?

I have a 40DCOE that could be a fitted to ncbugeye at some point.

I notice that the commonly available Cannon manifold sold by Pierce et al is a straight shot.

What are the space issues I might encounter?

Comments? Suggestions? Yes, I know, stick with SUs.
 

Attachments

  • 297200-Weber40DCOE6.jpg
    297200-Weber40DCOE6.jpg
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Re: Is swan-neck Weber Manifold as bad as Vizard s

I have a swan neck, I also have 2 other Weber intakes.
Like most of the stuff I read in Vizards book, it's all BENCH tested and not ROAD tested.
The swan is the best out of the 3. The short straight shot was the worst but according to bench flow tests, it's the best.
He also states that the 1.75 SU is as good as a 45 DCOE Weber.
Not on my car. I have just tried the 1.75 SU for the 3rd time with several needles and 3 different intakes.
I will not give up my Weber for any SU ever.
Believe what you read or believe the seat of your pants.
 
Re: Is swan-neck Weber Manifold as bad as Vizard s

Thanks, Frank. This is only a 40DCOE not a 45DCOE, but your experience is extremely valuable. The swan-neck also seems likely to be able to fit better into the Bugeye engine bay, especially as the carburettor has 2" stacks inside a 3 1/2" oval K&N filter.

So when I have done all the basic stuff to make the engine want to draw in more air, I'll get the right jets etc, and give it a try. I need a throttle linkage and fuel union.

I have the Braden Weber book so I'm really dangerous right now.
 
Re: Is swan-neck Weber Manifold as bad as Vizard s

Do watch out for those multi linked throttle linkage setups.
My Cannon Swan has a spot for the original throttle cable and it has worked fine for 10 years now. Well I do replace the cable every few years. I have also whipped up a piece of aluminum with a 90* bent in it to accept the stock cable. Just drill a hole in it so the cable stop just fits. Return spring on the cable end fitting to a screw on the inner fender well as a back up return spring too.
 
Re: Is swan-neck Weber Manifold as bad as Vizard s

Any chance of a photo?

I was thinking of improvising it from the standard cable, and noticed that the position of the arm assumes it will be pulled from below. Can I just invert the arm and make it pull from above? It shouldn't be too hard to make up a bracket as you describe.

The carburettor itself seems to have a fairly strong return spring on the throttle - is this not adequate?
 
Re: Is swan-neck Weber Manifold as bad as Vizard s

You'll want at least one external spring. The ones on the throttle shaft seem fine until you've got it running, then you'll find 'em near-useless... the hard way. I've even fabbed up spring and linkage plates from old Atari computer frames.
 
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