I have some 44 webers and was trying to find the venturi measurement.The only numbers are 4.5 i think. The reciept when i bought them says 28.If i measure across the inside I get 37.5?
Also where can i buy new venturis and jets from?
cheers

Call Carburettor Service Co. on 02 9747 4066, 240 Parramatta Rd, Burwood in Sydney

it would be highly unlikely that 44 idfs would come with 28mm chokes.
i think the secondary venturies have strange numbers like 3.5, 4.5 but the main venturies or chokes have big numbers like 32, 34, 36, etc which refers to the mm size of the opening, the chokes have to be removed to see the number which is a slightly raised casting mark.
there are plenty of good web sites with lots of weber knowledge bases just google weber.

http://www.redlineweber.com/Redline1.htm 

check here

Standard vents for 44's is 36
Standard vents for 40's is 28

Sadly Carburettor Service Co is having trouble getting bits and pieces for these now. I just asked for some and was told no go.

Rod Penrose "may" be able to help - he usually has a heap of Webers for sale at the nats.

Otherwise it is AC.net or some one.

There is Re-Carb 9476 4100 and Hardimans 9771 5877 that were recommended by Carb Service co - but when i rang then they said "good luck"

idas? idfs? dcn's? dcnfs?

nick?

efi!

Is there a way to tell what they are?44s or 40s.They are idfs.Thanks for the info guys.

down the bottom flange near the mixture screws there should be some stamped numbers.

Should say IDF 44 XXXXXXXX

The XX's are serial type numbers.

Should also say made in Italy / Spain

a