Join Date: Apr 2013
Location: Columbia, Missouri, USA
Here's how the engine overhaul manual would have you position the piston rings:
I'm a bit uncertain regarding the aa and dd lines. I'm guessing that aa is the axis of the pins? I read on the forums that you don't want any ring gap over the pin. The Hastings instructions address the offset of the gaps for the three components of the oil ring.
EDIT: My thoughts were correct. I found a YouTube video where the individual briefly discusses the thrust line. I should also mention that the Hastings piston rings that I bought from Classic Alfa measured perfectly on their gap.
1988 Spider Veloce (with lots of 3D printed parts)
Last edited by Shakey; 11-11-2017 at 04:43 PM.