"CamZilla", I thought that's what you might be talking about.

I'm not sure if it will clear you're pistons, but I can tell you from experience that I have installed a TrickFlow Stage 2 camshaft in an 86 Mustang with a set of the Twisted Wedge heads with no clearance problems what-so-ever. As you know, the 86's didn't have any factory valve reliefs in their pistons. The following are the specs on both cams for some comparison.

TFS
Duration @ .050 int./exh._____224/232
Lift int./exh._____.542/.563

Z303
Duration @ .050 int./exh._____228/228
Lift int./exh._____.552/.552

Of course there are a few more things to think about then just cam numbers. There are variables in blocks, head gaskets, heads, etc that will determine the final outcome of P/V clearance.