I also have the D15B7 block but i put on a D16z6 head and i do know that when i do a valve job i do it in the firing order 1,3,4,2 and not 1,2,3,4. and if im not mistaken after doing cylinder 1 you turn the crankshaft 180 degrees which means your cam shaft moves 90 degrees. Then do number 3 cylinder and turn the crankshaft 180degrees (means the camshaft moves 90degrees) then your ready for #4 cylinder and do them same so you can finally finish with the #2 cylinder. It would then be smart to put the #1 back at TDC and recheck your work following same formula. I also recommend using the .007 -.009 specs that were suggested for that engine. Hope this helps you

BS Racing