its not warped very much maybe a 2 mm
ok i read if i use a service plate and abrasive paper of 400 (waterproof silicon carbide and i placed paper of the surface plate and rub against the gasketed surface ...if the warping is not too bad it would be ok.
i will check the surface again with a better instrument
if i get the head machined will it have a higer compressio ratio
and will i need to use cam gears to bribg it back into timing range ???