Head porting

[Efrain68912]

I'm going to port the heads on my 912 myself. The engine is internally stock, with the only upgrades being Webers and a Bursch exhaust. Can anyone give me some advice as to how big I should go, and what else I can do to get better flow. The heads are sitting on my spare engine that needs to be rebuilt, so I can take my time (and thus, hopefully, do it right).

[mein12]

Hi Efrain, you really don't need to remove too much from the combustion chamber. You just want to unshroud a little around the intake valve.
You need to make a disc with two holes in it that will sit down against the head where the cylinder seats. Then get a tube with a valve that reads CC's. You can then match the combustion chambers.( CC the heads)
The other thing that you will want to do is port match the intake and exhaust openings.
If you are in California let me know. If not I can send some photos your way....JMB.