Piston & Rod on the left are from a GMC Big Block V6 {351}, the Piston in the GMC rod is the size of many of the V6 engines in cars & Trucks today, {this one is really a Yamaha 660 Piston, it cost me $1 but its the size that counts here}. tH really small piston & Rod on the right is from a 3 cylinder Suzuki Mini Truck Engine.