A 5.3 is nothing but a stroked 4.8, same bore.
If you want cubes, acquire a LQ4/9 bore out to a 4.030 bore and stroker crank. 408 doesn't sound too bad does it?
If you want cubes, acquire a LQ4/9 bore out to a 4.030 bore and stroker crank. 408 doesn't sound too bad does it?