Piston to wall clearance


New member
Ok building a open flatty got a .080 over weisco piston what piston to wall clearance should I have and what grit stone should use. Thanks
Any where from 1 to 3.5 thousands use a 360 stone to get close and a ball hone ( in reverse very important) to get wht you exactly want for clearance then once you fit your rings run a Plato hone 3 or 4 times down and back to make suers the scratches from fitting the ring your dual bore gauge make sure constantly check to see if the bores mearsures the same at top bottom and middle very important when u don't have much clearance
.0035" is what I've used.
Chuck's right, the R3 stuff can run closer if you like.

Now, Wiseco will recommend something like .004" endgap per inch of piston diameter - I think that's nonsense. With the 1 MM top ring, set it as tight as you dare (same as the R3 stuff.)
Be sure to break in the engine/cylinder right and the thing will rock.

Thanks and God bless,
Brian Carlson
Carlson Racing Engines
Vector Cuts
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