To add to the confusion....my 525 is a 2003 model but with only 180 hrs on it. Are the hours more important or the fact that it is approaching 12 years old on the valve train? I know I will pass the 200 hr mark in the spring.
Your 03 engines need a few more things done to them then the later engines need. Your engines have GM head bolts, composite head gaskets and the earlier, more failure prone headers. Starting in 05, the uh switched to ARP head bolts, Cometic head gaskets and a newer design header. You will need to pull the heads and surface them, where you can get away with changing the springs on later engines without removing the heads. (Unless they need to be removed) Those head gaskets have a tendency to push out between the cylinders and the fire ring eats into the head. I would also remain vigilant in pressure testing the headers.
Eddie
10-15-2014, 08:19 PM
