coolant flow: heads or block first?

[vikingpower]

What direction does the coolant flow with a factory style pump? I think its block first but just needed to be sure. If so, does anyone know of a reverse-flow unit so I can send it to the heads first? I'm building a high-compression shortblock for use w/92 octane. Thanks

 

[Blown88GT]

Yes, block first, then heads. I only know of a few vehicles with reverse flow, all Chevy's: Corvette, new Silverado, probably some others.