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I am rebuilding my 40 idfs - again.  :-(
I am trying 2 different jetting combos for my 1835 engine :
a)  60 idle / 130 main  200 AC / w/  55 AC pump inlet (IM's original jetting) or
b) .55  idle / 115 main and /200 AC.

But that is not my question  

I believe my problem is the floats.
I did CB's  "cooking with IDFs" conversion a couple of years ago , have undone that and sadly have mixed up the needle and seats. I do not see any markings on them.

So .... my question : with the above jetting combos (on 40 idfs on a 1835 engine) what needle and seat size for the floats should I use?

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I'm not sure what the question is? The needle and seat are not generally something anybody ever messes with, other than to replace during a rebuild, or to set the float height. I'm not aware of any various sizes, and can't think of why there would be. There aren't any "sizes" listed on CBs parts list.

The CB jetting chart is a great place to start. With a 1915, I think 55s are going to be pretty close. The 130s may be a bit fat, but you won't know without an AF meter (unless you go WOT, pull off the road, and read a plug).

I wouldn't get carried away with the correction jet.

Stan, when I did the "cooking with idf" upgrade from CB performance,  the the kit came with different size needles and seats for the floats. So I changed them as recommended to work with the kit's "larger" venturi .
I only had moderate success with that rig and have given up on it. I have taken all that mess out and gone back to the original geometry for the carbs.

But this leaves me with a couple of different needle sizes and seats with no markings. I don't know which fits in  the original 40 idf.
When I went to Pierce manifold to buy new needles and seats (along with the jets) for the IDFs, there were lots of different sizes.   So ... which size ? - is my question.

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