1750 105 and Alfetta 1800 are not the same bolt pattern. That's why i asked the question in the Alfetta forum.In the USA cars, the 1750 models (1800cc) had the same bolt pattern as Giulia 1600 or earlier 1300.
Down under, I don't know.
Alfetta GT/Sedan - 72 to 83 - same bore and stroke as the 1750, so 80x88.5I think these later small motors shared driveline components with the later 2 liter and the crank "should likely" be similar to the later 2 liter.
The design of the early 1969/71 1750 engine was an interim "fix" at the time, and shared early design to save $.
Which "1800" are you dealing with?
The Alfa 90 type (bore/stroke80x88.5) or the 155 version (84x80)??
These were never sold here so no direct exposure.