160 on the exhaust is a touch too high unless you are going to run over 8000 rpms. And the transfer ports are tricky. They usually have upwards and sideways angles built into them that are critical to maintain, and the transfer ports have to open at exactly the same time too. I have many times successfully changed transfer port timing, but in most cases I just leave them alone because they are a pain to mess with.
AV8TOR