E 28 535 compression

[ABARTH037@xxxxxxx]

I am trying to find an easy way to increase compression on my 85 535i. #1 are
there other big block heads that have smaller combustion chambers but the same
size valves?, 530, 533?  #2 Milling heads, if I was to get an adjustable cam
sprocket, how much can I mill of a head to get a considerable better comp
ratio (8.5-9:1), without fear of valve/piston interference.  And, does the cam
and head have an alignment mark, so i could at least get the cam close to
dialed in?  Detonation could become a problem with an increase in compression,
what is a safe ratio?  The car has a Turner Motorsports Chip and a header, if
that makes a difference?  Any help would be greatly appreciated. Thanks

Nathan
85 535i

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