Is the top of the stock 225 piston thick enough to cut a D style dish, and how deep could it go? Thanks!
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There are 7 to 1 "export" pistons made for the SL6 but those have a round dish... not a "D" dish, and it is still a (weak) cast piston.
I would not waste my time on doing and "fancy" machine work on a set of cast replacement pistons.
What are you trying to do??
(Based on this & past posting, sounds like you want to build a low dollar quench 225 SL6...,)
DD

Yea Doc, that's exactly what I'm considering. Here's what I'm thinking....

Based on factory numbers (and I have not yet measured out this engine), the head chambers are recessed into the head about .200" while the piston usually sits about .140" in the hole. If the 198 rods are used instead of the 225 rods, it will push the stock 225 piston roughly .147" OUT of the hole. This will give a quench of about .053" with a .020" steel gasket. Mill the head .008" to clean it up and I'll have about .045" quench. But the compression will be way to high. So if I cut about a 18cc "D" type dish in the piston tops I'll get roughly a 9.5:1 compression. I've seen this done to other types of pistons and assume it's possible. .045" is not bad for quench! But, as mentioned, all of this must be measured out on my specific engine(particularly negative piston deck since as you mentioned, it varies between engines, as well as the 198 rod to 225 piston skirt clearance).

I suspect this will work if I can dish the pistons. I'd love to find a piston already like this. The KB268 is close, but the CH is too low. I don't mind the idea of the stock 225 piston as I don't plan to rev beyond 5K anyway.
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