I'm building an S52 (sort of) out of an M50NV and S52 rotating assembly. I noticed the piston sits ~0.032" (0.81mm) above deck, however I can't seem to find anyone else that measured this to confirm... It seems like kind of a lot. According to my math, though, it is right?
And can anyone confirm that the deck height of these blocks is 210mm?
89.6mm stroke / 2 + 135mm rod + 31.0mm piston comp height = 210.8
So if deck height is really 210mm then I should be spot on.
Then comes the issue of calculating compression ratio... I can't seem to find the volume of the dish in the piston (all of the links I find in old threads are dead) nor can I find compressed HG thickness.
My head had to be taken down 0.013" which is 3 thou over BMW's spec (rules be damned!), which the machine shop said wouldn't be a problem. Can anyone back up this statement?
Valve to piston clearance will obviously be checked.
tldr:
should the piston stick out .8mm?
what is the piston dish volume?
what is the compressed HG thickness?
should I buy a new head?
And can anyone confirm that the deck height of these blocks is 210mm?
89.6mm stroke / 2 + 135mm rod + 31.0mm piston comp height = 210.8
So if deck height is really 210mm then I should be spot on.
Then comes the issue of calculating compression ratio... I can't seem to find the volume of the dish in the piston (all of the links I find in old threads are dead) nor can I find compressed HG thickness.
My head had to be taken down 0.013" which is 3 thou over BMW's spec (rules be damned!), which the machine shop said wouldn't be a problem. Can anyone back up this statement?
Valve to piston clearance will obviously be checked.
tldr:
should the piston stick out .8mm?
what is the piston dish volume?
what is the compressed HG thickness?
should I buy a new head?
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