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+--- Thread: Slipper piston clearance (/showthread.php?tid=445)
Slipper piston clearance - Zetomagneto - 11-11-2017
Can someone suggest suitable clearance for the excellent Slipper pistons sold by Tony.
I am having a block bored next week and would like to know the recommend clearance.
I know the Honda pistons have a very close clearance, something like .ooo4" if memory serves correctly, these being low expansion high silicone pistons.
I don't want excessive clearance, but don't want pickup or seizure either!
I know several on this forum have used these pistons, what are your experiences with them?
Thanks in advance for any and all comments
RE: Slipper piston clearance - Zetomagneto - 12-11-2017
Am I the only one using these pistons!
RE: Slipper piston clearance - Steve Jones - 12-11-2017
(12-11-2017, 08:23 PM)Zetomagneto Wrote: Am I the only one using these pistons!
I asked this very question of Steve Flake back in 2013. I still have his email reply which says bore to whatever is engraved on the piston crown +/- 0.000.
Done that twice since and it's worked perfectly - but run it in carefully.
Steve
RE: Slipper piston clearance - Alan - 12-11-2017
For race engines, I get them bored 2 thou more than the size on the pistons, to give a bit more clearance, but Steve is correct - the size on these pistons is the size the bore should be, not the piston diameter.
RE: Slipper piston clearance - Zetomagneto - 12-11-2017
Hi Steve, and Alan for your helpful replies.Having now miked up the pistons and comparing the diameter of the skirt with the dimension on the piston crown gives a clearance of .079 mm or .003".
Will get the block bored as per crown, in my case 57.75mm.
Thanks again.
RE: Slipper piston clearance - Parazine - 13-11-2017
I've been using these pistons in my lightly tuned Chummy engine for the last year. They are excellent! Virtually no oil burning, good performance. Block was bored to the size indicated and carefully run in for 500 miles. Highly recommended.