Outer Limits 4x4 Board

G'day
im just about to re ring my sierra and ive been given a set of higher compression pistions 10:1 they are swift gti pistons and they have the 4 recess in the top of the piston for the valves. I thought that all G series engines were a non interfrence motor, so i shouldnt have any problem using these with a 8v head? or am i just going to bend the valves?

mundy

your first hurdle is that gti pistons have 19mm pin and the sierra is a 17mm pin, so you would need gti rods to fit the pistons. on ebay there are frequently flat top 'samurai/swift' 9.5:1 pistons from the states with rings for au$100 + post.

id say since they dont have a the notch the would give you higher compression than gti ones in an 8v head (16v combustion chambers are heaps smaller hence higher compression)

side by side 8v and 16v apear to have the same ring spacing and deck/pin centre buts hard to be sure since the pins are differrent

hope that helps