I have a fairly fresh 355 sitting in the corner of my garage...i've been tossing it around to build it the rest of the way and throw it in the camaro in the spring. I have a set of 113 heads off an 88 vette that I would like to use. Problem they are 58cc heads... do I need dished pistons? I don't want much more then 10:1, the motor currently has flattops with the reliefs cut for valves...help me out guys. I'm starting to do some home work for this build so let me know

The ZZ4 has 10.1:1 compression with those heads and flat top pistons, but it does so by having the pistons about 0.030" in the hole at top dead center, and by using 0.051"-thick head gaskets, which make for an extremely undesirable 0.081" piston-to-head clearance, That's twice what it should be. But you may be able to run 10.5:1 if you choose a big nasty cam, or live at high elevation, like Denver. Also, some machine shops can do what's called a sweeper cut, to unshroud the valves. This is a good way to add about 4 cc to the combustion chamber volume. So, first, go measure to see how far in the hole your pistons are at top dead center, then go from there.