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Discussion Starter #1
Who has done their own piston work?

What is a good way to blend or modify piston domes and valve reliefs? How much clearance should there be between the piston and the cylinder head chamber?

What do you use to blend your piston domes, edges, etc?
 

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Martin,

If the chamber has been CNC'd, I like to have the dome clearanced MIN .020" at any point in the whole profile of the chamber, at ZERO piston to head clearance.

If the chambers are not all exactly the same, shaped by hand, then it's just a more difficult, time consuming job.

As for doing the actual shaping, I like to put the piston in a soft vise, and use a variety of carbide burrs, and, or, a variety of abraisive tootsie rolls. You need something to hold the piston tight, so you can concentrate on what you're doing. When I'm done shaping I like to use emery cloth over all the edges and top and polish/smooth them all out.

For Valve Reliefs, I assume you're talking the brows, I like a generous radius on the intake brow. The exhaust brow is not as critical in terms of the radius.

Gotta run!

Chris
 

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Discussion Starter #3
Thanks I appreciate the info.

The heads were done by hand. So I am going to have to fit each piston to its chamber. Then make sure I mark them so I can remember where they go when I decide to put this thing together.
 
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