in basics Paul,
To increase topend u must retard the cams, low end advance. if u apply it to both cams u shift the power up or down the rpm range.

usually a 4 deg on each cam from std point will shift power abt 500rpms up or down, but that means the whole cam profile will shift, so if ur cam has a working range of say 2000 to 5000, it will be 2500 to 5500.

but ur only option is by trial and error i guess. But do test clearances before u run.

__________________
Jay,
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