it is a blueprint of the cyl. port heights and widths. i just want to build my engine as good as what the factory spec is. just a little project for this winter.
The sleeve manafacturers have to start somewhere, I wonder if they work from spec's or actual cylinders or both. Good port shop maybe your best option.
You have to extract the data from the specs area of a service manual . It gives comp ratio exh timing , inlet timing etc. Then you have to do alot of measuring to see what you have and compare it .