Just a quick tip on those new heads or port jobs.
You should make sure all the burs have been removed on the intake and exhaust ports, head areas and anything that has been worked. I have bought both new heads and ported heads to find quite a bit of small bits left behind from manufacturing and porting. These little buggers are the small scratches you will find in a new mill but would never know it until tear down.
Here are a few photos of a recent build that was cleaned before install.
If you look closely you will see the bur line on the tip of the fin.



Here is the bits after cleaning:


You should make sure all the burs have been removed on the intake and exhaust ports, head areas and anything that has been worked. I have bought both new heads and ported heads to find quite a bit of small bits left behind from manufacturing and porting. These little buggers are the small scratches you will find in a new mill but would never know it until tear down.
Here are a few photos of a recent build that was cleaned before install.
If you look closely you will see the bur line on the tip of the fin.



Here is the bits after cleaning:

