RC, I wonder if SHK makes the cylinder inserts and pistons. The inserts should be the same. I believe the pistons would be somewhere between 8.5 and 9.0 to 1 compression ratio. I understand FVD Germany makes them or obtains them from someone. Just as an update. I have received the Ruf titanium conrods, GT1 oil pump and GT3R valve springs. I have on order the GT3 Cup heads, valves and tappets (lifters). Still working on the cams and 3.9 kit. Once I have everything we will start the machine work (port/polish heads and machine for metal o-rings, cross drill/knife edge crank and boattail the case.) This will be followed by ceramic, dry lube and heat dispersant coatings. When all this is complete we will break down the present motor, balance and re assemble and see what we get.