For a 1000 Hp I would suggest the Olivers. BUT keep in Mind that Molnar and K1 were both started by the same guy. They both come with ARP 2000 bolts. The Molnar also has the option for what they call Power Adder and Power Adder Plus where they add more Material to the beam. Actually they machine less. This makes the rod a bit heavier but also stronger. You could also look at the Pro Series from Manley.
Todd