[ultraflo]

I wouldn't go past 150hp, until you really get a handle on the tune... I got just over 60 passes on the stock block before it split down the middle, using an NX EFI Race kit (single nozzle before t.b.) jetted @ 200hp. Some of the stock blocks last longer, while others (most) only last a few passes at that level.

I'd say that 175 is the most you'd wanna spray on the stock bottom end... and that's really pushing the limits.