C15 what motor Serial numbers can you upgrade?

Bigexpress is right, the gain just isn't there. We have a 2000 379 with a 1MM 600 with a harness and a ecm tune with a B/W turbo I forget the number but ecm says .5 gpm higher than reality. Now with all that stuff 4grand you might say, in a fresh engine that is right I won't settle for close we gained .5 in real numbers. Ecm says we gained 1.0. Again if the engine isn't proper "tuned" mechanically and electronically and any aftermarket parts matched to the "electronic tune" you aren't doing the engine any favors. Most of any fuel millage enhancement drug is just aspirin in an over labeled form. The electronics of the 6nz and Mbn are not that different. The compound turbo set up on the acert is a good set up. They are just very fickle little details are big to them.

 

I have a MBn flashed to 6nz. Looking for 650-700 hp with stock file. What upgrades and part numbers?