Im doing a d16/vitara build and got my z6 head decked 0.020 and was going to deck the block 0.020 to bring the compression up to about 8.1:1. Well i got the head back from the machine shop and now it looks like the deck has opened up about 0.030 around the valves. So is this head still usable or do i now have a large paperweight? I found in the service manual (after i got it decked :1) that the maximum you can deck the head is 0.008, but i assume this means that anymore and the stock valves and pistons could contact.

 

yes

 

you can deck the head .072 without issue as long as you check valve/piston clearance

NonVTEC SOHC registers