Originally Posted by richm
just as a reminder... may be useful to get back to an early stage of the discussion that we've maybe strayed from..
Rich, I agree the discussion is very interesting from a technical point of view, but I think a few valid points were made regarding resurrecting otherwise scrap heads. This is probably of significant interest to quite a few people since decent quality heads are rarer than hen's teeth.
Originally Posted by richm
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Quote from Stu:
Brad,
Its a misconception that the head becomes "Too thin, or weak" and also that its about the altered "Compression Ratio"
The issue is the area around the valve seat becomes dangerously thin after 138.68mm.
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the compression change isn't so much the issue as the machined face breaking into the valve seats... (compression increases to about 8.2:1 for a 0.5mm material loss).
At which point does the increase in C/R become an issue on a stage 3 engine running an off the shelf chip ?
Would live mapping be required to counteract the increase in compression ratio ?