Hi all

Does anyone recommend a resource for ported intake exhaust manifold gaskets?

I was opening the intake holes on one 240Z gaskets on a spindle sander and I have mixed feelings about the results...
I thought I had seen some larger diameter intake exhaust gaskets on the net somewhere but can't find them anywhere now

240Z intake gasket port hole is about 36mm
I need to get to 40mm for my specific application...