Weber question

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Jerry Havel
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Joined: Sat Aug 02, 2008 11:43 am
Location: New jersey

Weber question

#1 Post by Jerry Havel »

If anyone is using Weber 40IDF carbs on a 1600 cc engine, can you tell me what size venturis you are using? My Webers have a 115 main jet, a 200 air corrector jet, and a 55 idle jet. These all match relatively closely the jets in a Solex PII-40, but the venturi in the Solexes is 32 mm, my Weber venturis are 28.
jerry havel

Norm Miller
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Location: Ft Collins CO

Re: Weber question

#2 Post by Norm Miller »

Use them as they are. If you later think you need more top end the 32 might improve.
 

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Daryl Bruhl
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Location: Grand Terrace, CA

Re: Weber question

#3 Post by Daryl Bruhl »

Jerry, My car ran fine for years with that ,out of the box set up' (although 50 idle were standard) 55-I are better. I thought maybe 115-M ran a tad lean ,SO, trying you name it jets, tubes and venturis you get to a point where you want to quit. Then you drive it for awhile with new set up all is fine until you start reading more and learning less. A lot of combos work well, some better than others as you will learn. Testing with seat of the pants technology is fine although sometimes your head gets so close you wonder what happened to the nice spring time freshness. MY set up for now ? is 30mm-V, F11, 125M, 200A, 55I. Your 28mm venturis can be enlarged with sandpaper wrapped around 1' piece of dowel. Copy the shape that is there and have a tool to measure inside diameter. Keep in mind smaller venturis will help keep the low end power need in every day driving.
enjoy 63 super 90 sunny SoCal
Daryl Bruhl

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Walt Nolte
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Location: Mountain States

Re: Weber question

#4 Post by Walt Nolte »

On a 1720 cc 912 engine with 123 Ignition, 40IDFs out of the box, except 110 mains and F7s. Runs great, but at 3500 feet of altitude.

Walt Nolte
59 A Coupe
Montana
walt nolte

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DonCichocki
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Joined: Thu Aug 22, 2013 4:29 pm
Location: Lafayette, NJ

Re: Weber question

#5 Post by DonCichocki »

Put an A/F gauge on your car with F7's and you will see you are running VERY rich below 1/3 throttle, especially at your altitude. I know what John Willhoit says but the gauge doesn't lie.

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