The air cleaner reads 351 4V on my '71 Grande'. This is confirmed by the fifth character in the vin "M". What does 4V represent? If they meant 4 barrel, why not say so. Please be bear with me, this my first Mustang :) And I must say, I have been converted!
Thanks
mike
The air cleaner is huge. They didn't name it 'Grande' for no reason.
"V" stands for venturi. The word was popular years ago, but the word "barrel" kind of took over. Maybe it's just easier to slide off the tongue, who knows......
V = Venturi "Barrel" is a popular term for the carburetor throat. There is one venturi in each throat...
They are not quite an interchangeable term, they refer to two different very distinct parts.
"Barrel" is a popular term for the carburetor throat. There is one venturi in each throat. A "venturi" is a tube with a restricted section. When liquid or air passes through the venturi tube, the speed of flow is increased at the restriction, and air pressure is decreased, creating an "increase in vacuum" (a reduction in ambient pressure). This causes fuel to be drawn into the barrel. The venturi action is used to keep the correct air-fuel ratio throughout the range of speeds and loads of the engine.
That makes sense and thanks for the reply. Had a ' 71 240Z once with SU side draft venturi carbs. I guess Bernoulli got it right.
mike
Ermmm.... looking down, let's say a Motorcraft carb, in each throat we see a venturi making up the throat itself (the shape is unmistakeable). Within each venturi, we notice a booster venturi suspended on a small pylon in the centre of the main venturi...
Looks pretty much like that with a small pipe in the center of the booster venturi. The booster is a small ring shaped device correct?
Any idea on CFM rate.
Thanks for your advice.
mike
The booster venturi is the small ring in the middle of the throttle bore.... The throttle bore is also shaped like a venturi (which, I guess, makes it a venturi). For a better understanding, Google "Bernoullis Principle" - check variations, I can't spell Italian for squat...
Unless my memory has really gone for a crap, the 351C 4V used the Motorcraft "spreadbore" carb... IIRC, this was in the 600 to 700 CFM range.
Disclaimer.... there's been a LOT of water under the bridge since I worked on these regularly.... if I'm wrong, I plead the Alzheimers amendment...
Your spelling is perfect, Bernoulli's.
In this case, the carb is an Edelbrock but don't know what model.
mike
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