Ddec 4 cam swap experience

Hey.
I've got a early ddec 4 that is set from original 430/470 to a compatible factory 500 tune. I have had 5915 injectors and 171702 turbo for a while and truck ran pretty darn good just always want more.

Had a 4912 cam swapped in while I took family on vacation last week. We had to ream the threads from the cam gear hub to fit the 20mm bolt as per Erich for SS60 recommended. Also added Jake's while I was at it.

Truck idles like a sewing machine but once I picked up a load I wasn't that impressed, noticeably less lugging/ recovery @1400 rpms. May only pull slightly better over 1800 Rpms than before and just doest quite feel right.
I'm wondering if they retarded the cam gear a tooth while reaming out the hub, anyone have thoughts.
Only other thought is if ecm program needs to match cam as i didnt change it yet.
Thanks for any thoughts, Bo

 

Erich thought a ecm program was needed also.

 

Injectors were set with 81mm tool for this cam, mechanic assured that it did not jump time but no lobe timing procedure was done.
I'll be in this Louisiana oil patch for a few weeks recouping some money to decide what to try next.
Appreciate all the input.