hi so i have recently installed a weber 34 adm of a ford xe/xf which has a 4.1l engine and i though i would add some pictures and jetting i used that got it running really good.



original manifold.



now ported to suit adapter plate with a die grinder.



with adapter plate on top.



after installation.









the jetting i have used are the following.

primary/secondary

idle:50/55
main:150/150
air correctors:180/160
acc pump:60
emu tubes:f66/f66
aux venturies:4.50/4.50

i am running 10 degrees of timing and idles at a smooth 750rpm with these jettings the pick up is excellent with no flat spot or hesitation, also reading the spark plug it shows a tanned colour.

The only problems I have encountered are from rest if you floor it will bog down but once you start of then floor it its fine (people may contribute on a fix?)

in conclusion i think this was the best thing i have done since I got the datsun I was abit concerned that the carby might affect low down being so big but it has excellent low down power not even comparable to the stock carburettors I had on it.

Thanks for the pictures and writeup. It's quite inspirational!
I'm sure that the jetting will be a big help for loads of people.

Maybe consider soldering up the acc pump jets, and redrilling them with some 'number drills' from smallest to largest until you are happy. This will improve the 'from rest' performance.

I'm sure others will contribute further suggestions. I've not worried about carbies since 1993.

When you press down on the accelerator, it is the accelerator pump circuit of the carburetor that is mostly involved. The 34/34 is a fairly big carburetor for a 1.2 liter, so it needs special tuning for sudden throttle changes.

Bog is what happens when it is too rich. Hesitation is what happens when too lean. So perhaps you need to change the pump jet to a smaller one.

hi thanks yes the carby seems to run really good with these jets anything smaller in the mains it has lean spots.
i am looking for a size 50 accelerator pump jet to try but i guese somethings cnt be perfected without a dyno.

but it doesn't really effect me as you don't need to floor it of the line to get it going it has good down low power once it gets going you can floor it no problem. Its only say form dead stop or if you hold the brake and floor it it will bog down. but no doubt i will try a size 50 accel pump when i get a hold of one and post up the results.

Thanks!

No dyno needed. Just a little work to obtain the parts and try them. Keep going, you're almost there!