[Andrew7dg]

I will explain...

The pistons from your 4g63 will not work because the bore of the 4g63 and the 4g64 are different.

4g63 85mm
4g64 86.5mm

So no... the 4g63 will just slap around in there

You will have to buy aftermarket pistons for the 4g64 if you want to do the hybrid combo

If you want to do the stroker combo (4g63 block/ 4g64 crank) you will have to buy aftermarket pistons as well

but what are you trying to do is the question...