Are the head templates in the Powersource Book to scale?


Active Member
Are the head porting templates that are drawn in the Powersource book to scale? The templates seem to be smaller than non ported heads! For example, the height and width of the intake port is smaller on the template than a non-ported intake port.

Has anyone else run into this problem?

as I recall, yes

You can compare actual measurements with those noted and get an idea as to how much paper stretch there may be...not much in my book...note that the book states they are for guide purposes only.
Perhaps there are two different versions of the book? I seem to vaguely recall seeing a picture of fold out templates on large pieces of paper. The only templates in the book that I have are on pages bound in the book and they do not have any dimensions on them.

Maybe the book I have is missing these fold out pages that have the templates to scale?

When I use the templates that are bound in the book, the templates tell me that I need to ADD material. A fair bit too.