Anybody recognize these 340 pistons?

They are probably 1.84(that would be best case scenario) 0.60 down the hole with what looks to be a felpro gasket which would put it below 8.5.1. with a 70 cc chamber. Measured alot of this stuff up years ago , silvolite , badger ,ohio etc before kb and others offered other choices and you would be surprized how low everything was. In order to be around 10.5.1(68-71 two valve relief high comp piston) with a j or x head you need to be out of the hole , do alot of milling, replace tulip valves etc. The common 4 valve relief piston (factory or rebuilders) do not offer much for performance