Today, I finished the new, 2mm bigger, inlet and outlet valves.
On the right side is the inlet valve as it comes out of stock. Original its from a Seat.
And at the other side it is in an optimized form. With an inner correction of 30°.

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ImageShack.usOutlet Valve. The problem was to find a Valve with the same ... in the correct size. So I took a valve from BMW which 3mm too large and worked with it extensively on the lathe.
Here is on the right side a picture of the valve is in the form of original BMW. I've just been ground down the outside diameter fits.
On the left side you can see where I turned(?) (Whats the verb of lathe? to lathe???).
the lower part of the shaft I thinned.
Change the radius to the valve plate down and and the valve disk I made thinner.

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ImageShack.usThe next was an inner correction with 20° and an inner correction with 30°.

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ImageShack.usAt last I grind an outer radius at the valve disk.
picture without radius:

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