Gandini piston

[Vink27A]

Thanks, it indeed looks like it's bored to mil. standards. So the military used another piston with a smaller diameter, Gandini offers a piston on there side of 69.00mm but with another top without valve recesses. It might be this piston they used.

I used a 3D optical measuring machine (Werth) with an accuricy of 0.0003mm (L50) but for this a bit over the top

[SPRIDDLER]

Gandini offers a piston on there side of 69.00mm but with another top without valve recesses. It might be this piston they used.

According to their catalogue the Hepolite piston for standard compression ratio (6.3 : 1) for the years 1948 to 1955 had a cone top without valve pockets. The high compression piston (7.5 : 1) for the same years had a domed top with valve cut-outs.
See page 32 here:

http://archives.jampot.dk/technical/Pis ... 4-1963.pdf

[Vink27A]

Thanks, it makes a lot clear to me, we'll use the Gandini piston and set the bore diameter to 69.1-69.12 mm.

[raffles]

You may like to know that T&L Engineering always bore to plus five thou on Gandini pistons
hope this is usefull
Tony

[Vink27A]

Thanks Tony, I will hone it to 69.013mm (+0.12mm/4.7thou")