Arias Pistons PN A3310404 are associated with three different applications depending on what combination of block and head you choose to combine as listed below:
B18/B20 With B16A Head:10.0:1
B18/B20 With B18C Head:10.2:1
B16A with B16A Head: 9.1:1
B16A with B18C Head: 9.2:1
Pin Size: 21mm
Bore: 81.5mm
Rings are included with the Piston Set
ARIAS pistons are rated at 650+ hp. but here at Golden Eagle, we believe in overbuilding. If you plan on hitting 600+ hp. we would highly recommend the upgraded pin option.