Greg
I bought a new dipstick from Summit (something like this:
http://www.summitracing.com/parts/fm...c303/overview/). You could probably get something similar locally. It is a replacement part and is dimensioned the same as the original dipstick that I removed. It would give you the right level without having to calibrate. I use just over the 5L mark at each change.
For what it is worth, my
oil pressure runs around the 350kPa mark at running temp. It picks up to the 400kPa mark at full noise. That is with all new brearings and rings.
Geof