DOHC ZC Tear Down Here's a DOHC ZC block that I was tearing down to pull the pistons and rods from. The plan is to use the PM7 pistons and rods in a new engine build consisting of the SOHC ZC block and the D16Z6 head. The large domes on the PM7 pistons make 9.x:1 compression in the 43.8cc DOHC ZC combustion chamber. When you put those same pistons in the 34.6cc combustion chambers of the Z6 head, you get around 12.3:1 compression. That compression is easy to hold on premium pump gas (93 octane here in Texas) with halfway decent tuning, and will yield nice power gains once the head is opened up. One thing to note is the full length crank girdle. The 92-00 D blocks don't have full length girdles (I think, someone let me know), so they aren't as stable as the 88-91 D blocks. Images on this page are approximately 70kB to 100kB (600x450) each, and are clickable for more detailed 275kB - 290kB images (1280x960) in new windows.