[gumby79]

Well done I see more progress.
The rotating mass reductions you have pursued add up to ~60#, I'd venture to guess equates to ~500-1000# of static weight reduction

The 04.5-07 pistons have some special design for emissions

Non EGR CR Cummins duse not exist.
I found this out when researching parts for an 05 medium duty Cummins with a misbehaving EGR valve the wealth of information that is the internet could only tell me I was not seeing what was in front of me and EGR hit the Dodge/light duity in 04 the physical valve didn't show up until the 08.
Re cam the motor is the only way to remove the non cooled exhaust gas non-recirculating system. By closeing the exhaust valve early they were able to trap spent hot exhaust in the cylinder displaces fresh air on intake stroke making a valveless EGR
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, I can pull 6th @35 mph running ~900 rpms. never a complaint unless the hill is too steep

How is the 64mm(?s364?) Spooling ,at the extreem low rpms?on grades(5-9%) my 91 with an hx35w12 with a Quick Spool Valve sends in a written complaint using smoke signals running less than 1263 RPM( 55mph in 6th 2ndOD.61, 3.55rear 31.7"tire) due to insufficient air to make power from the fuel causing a rich condition and overly high egts for throttle position and speed 850-1050° ,by 1050@10psi is turning black, drop to 5th(.71 1470 ) 650-750°. Or run 66mph (6th.61 1516)and she spools 15-20psi depending on the grade.
IAT 70° ,that would be a wet dream -2to 20 above ambient with the itty bitty baby intercooler the first gen came with.worst seen so far this winter (its been mild) 11° air filter, 120° post compressor, 9°f IAT @70mph crossing the ID/MT Continental Divide pass