I've been looking into the 5" bore space stuff a bit - I know Brodix and Donovan make 5" B.S. blocks but i can't find any information about stroke clearances/ options or the minimum cylinder bore these blocks come with and what you can bore them out to...? - trying to compute for displacement...

Dart makes an Iron 4.9" B.S. block but i don't know of a head manufacturer that makes a 4.9" B.S. cylinder head... i don't even think dart does - does anyone know?

When going this big, how do the cast aluminum Donovan/ Brodix blocks handle things? they are cast and I keep hearing the cylinder walls move quite a bit