Pistons specs question for 340 build
Yes, a lot of people neglect that small space between the top ring and the top of the piston. The only way to work your engine out accurately is measure everything on your own engine yourself, with cc'ing equipment or make up your own stuff like I have. Most people won't have a pipette or burette but some various size syringes are a good start: 1ml = 1cc, so syringes in 1ml, 3ml, 5 ml and 10ml are a good start + obviously a depth gauge, which most digital vernier calipers have built in. Checking a piston dish cc is easy but working out a dome is more difficult. If a manufacturer states their dome is whatever cc then this shouldn't be taken as error, it should be taken as correct, but measuring at least a few to be certain, for peace of mind. I would probably use some Play-Doh or Clay to get the dome to make an impression and measure that space with the kit. I'm sure you guys have your own ways.