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2012 5.3 rebuild, Major OH? with Non-AFM parts.

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My son's GMC 1500 with the 5.3 is on its last leg were told. its been having the low oil pressure issue's , did engine flush with lasted for a 4 months, Now he came home and started with and it said 0 oil pressure. took it back to same shop and they replace the sensor and screen, they told him its on its way out, has low OP. This truck has 123k on it. Any way he plans on having it rebuilt at the same machine shop I had my boat engine rebuilt. This guy is a race car engine builder, has been for years, and very methodical in his work.   Plan is to replace AFM parts with Non-AFM parts, performance cam, lifters. and what ever else it needs, if this guy says its needed, it gets done.. Major OH.  Any recommendations for cams  and tuning? I've read it will need the ECM software re tuned for non AFM  parts and also for the performance cam.   Tunner suggestions?  I would like to send ECM out while engine is being rebuilt. Any other tips while engine is out?


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Here is one problem, you can't just send a computer out and get tuned and plug it back in.


There is no "canned" tune in the world that will just work because you installed an aftermarket camshaft. The whole calibration after the change is custom to this vehicle. I've tuned many vehicles and none are the same. The process to calibrate the airflow model and fueling is the same but no two vehicles ever took the exact same changes.


It's best to have an in person tune done or one at a shop that deals with these types of swaps.


As far as cam sizes go, stay small if you aren't changing the torque converter to a higher stall. For sure want to stay at or under some in the 212/218 range with a LSA of 114 or so. There are several cam choices out there in that similar size.

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