Potential method for setting weber floats without special tools
 

I was thinking of a way to set the float height very accurately using only a vernier and some simple math. I understand that the mechanical way of setting the floats is not very accurate given the different specific gravity of new fuels as well as variations in float dimensions and weight. I figure that you could very acurately remove the issues of fuel sg and float weight/dimensions by filling the bowl with fuel up to the desired height with the fuel you will be running in the car and then adjusting the tab or shimming the needle valve to be just closed at that position. All this would be done on a level surface but should give pretty good results. Is there anything I am missing??

Ok but start by checking the floats weigh whats stamped on them and are dimensionaly the same. The floats for the 2 DCOEs on the other car had the 26gr stamp but one weighed a couple of grams more (dunno how).

I just realized that I don't know what the "perfect" fuel level would be inside the bowl. Has someone every translated the optimum level on a float gauge to a measurement down from the flange of the carb body?

Surely the delivery of fuel from a given jet will also vary with the SG of the fuel so even with the float set 'accurately' the metering will be affected.

I would have thought setting the nominal value to within 0.5mm would be OK as long as all float heights were the same ?

Well I have mine set dead on as per the instructions of 12.5-13mm (float above carb body) and needles at 18.5mm (accounting for gasket thickness). I just was thinking that these numbers are only valid with 4 absolutely identical floats both in weight and dimensions.

Mike-72

I bought two float gages. One for each reservoir. That way, with the engine running I can check both quickly and make the final adjustments. Avoids swapping, and minimizes the fuel draining mess.

Ultimately, you have to check with the carbs mounted and engine running. Static setup will get you pretty close though.