5.9 magnum rebuild questions
Lastg time I rebuilt a 318 I did a 40 over 408 striker and a massive cam so I wasn't worried about compression. I want to keep this as stock as possible it's gonna be a daily. I'm saving the next 408 build for the 84 ramcharger.
The 5.9 flexplate has the weights welded onto it for the balance compensation. You will definitely need it.
Looking at those photos of the bores, that block should be bored to the next oversize. Hopefully, everything cleans up at .030, if it hadn't been rebuilt once before. An oversized bore does not really contribute to the compression ratio - that is more associated with piston height, head gasket thickness and/or cylinder head volume, which can be influenced by milling the heads or massaging the combustion chamber.
Looking at those photos of the bores, that block should be bored to the next oversize. Hopefully, everything cleans up at .030, if it hadn't been rebuilt once before. An oversized bore does not really contribute to the compression ratio - that is more associated with piston height, head gasket thickness and/or cylinder head volume, which can be influenced by milling the heads or massaging the combustion chamber.
Last edited by AtomicDog; Aug 24, 2017 at 12:35 AM.
Your stock 5.2 ecm will allow the 5.9 to run but it will be lean and not have the power because the ecm isn't tuned right. You will need to either get a ecm from a 5.9 truck or get your stock ecm flashed for the 5.9. Hemifever is the person that can do that job for you. http://www.hemifevertuning.com/
Yes, 2003 was the first year for third gen HD trucks. So long as they both have the same number of drive wheels (2 or 4 wheel drive) it will bolt right in, hook right up, and down the road you go.











