I’m about nearing reassembly of my top end. Been one thing after another with this. Started as exhaust work turned stud extraction which then turned pulling the heads for metal chips. 2 head gaskets damaged in the mail, heads arrived with light scratches (found a nasty crack in an exhaust valve) which should be negligible with copper gasket spray. Machine shop turned my lower into scrap aluminum by rushing a gasket match/porting job out of the door asap.
I’ve got the tools to port my own lower which looks simple enough if you port match. They say gasket matching is easier but you remove much more metal which makes it tricker.
My question is this: the company I got my reconditioned/rebuilt heads from only had #105 which are step above #90 LS6 style springs only in seat pressure. The website states the #90 springs have a higher spring rate.
While I’m in there I’m gonna replace all 12 pushrods. No new cam or lifters. I’ve always read zinc additive is needed when breaking in stiffer springs.
What should I do after adding the additive? Change oil after 500-1000 or do my usual 6k? Current oil has only a few hundred miles but has been sitting with no heads since late December so I’m unsure of moisture accumulation.
I’ve got the tools to port my own lower which looks simple enough if you port match. They say gasket matching is easier but you remove much more metal which makes it tricker.
My question is this: the company I got my reconditioned/rebuilt heads from only had #105 which are step above #90 LS6 style springs only in seat pressure. The website states the #90 springs have a higher spring rate.
While I’m in there I’m gonna replace all 12 pushrods. No new cam or lifters. I’ve always read zinc additive is needed when breaking in stiffer springs.
What should I do after adding the additive? Change oil after 500-1000 or do my usual 6k? Current oil has only a few hundred miles but has been sitting with no heads since late December so I’m unsure of moisture accumulation.
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