Cp4 and Cp3 Timing

[Ne-max]

Can some one please explain to me why you have to time a cp4 on a LML and a cp3 on a Cummins. But Not on previous Duramaxs? Some say it's the stroke of the pump to injector firing on the cummins. But still seems odd to me. Do you time a cp3 on a cp4 swap?

 

[PureHybrid]

I have never timed a cp3 on a Cummins.

 

[kiwilml]

I didn't time my cp3 when I put it in my lml..

 

[Dallas S]

8 cyl divisible by 2/4

6 cyl divisible by 3