When a cylinder spacer is used to lower the compression, the cams are moved forward slightly, the engine will still run well but for best performance we have discovered that having a peak lift value of 112 degrees ATDC for the inlet cam and 112 deg. BTDC for the exhaust cam will yield the best power increase.  
 
Fitting these cam sprockets gives you the ability to dial in the camshafts to this optimum setting. Please note that you will need a dial gauge and degree disc to carry out this task.