My 2-572" shortblocks were built to handle 1,000 HP. We built them using Merlin 345VR heads, 8-71 blowers, no intercoolers, Nickerson 980 carbs, special Crane HR cams. This combo dyno'd at 780 HP @ 5,500 and has been very reliable, but we need more power.
I have $10,000 (total) available for engine upgrades; what would you upgrade and with what parts?
Thanks
Due

Buy 2 Intercoolers and run more boost. Aside from that, $10,000 won't get you much if anything inside the motors and it sounds like they are built already.

These should do the trick: http://www.cpperformance.com/detail.aspx?ID=5249

are you underdriven, overdriven, or neutral on the pulleys?

we must have been writing back at the same time. That's where I was going too. If you are neutral or under-driven especially, intercool and boost up will yield the best return.

Spare parts!!

Put the money in a sealed container. Wait for an outgoing tide. Put it in the water so it will float across the lake to your neighbor. Then get the enjoyment of watching him spend it!!!!!!!!!!!!!!!

Little pulley on top, big pulley on the bottom!

Another option might be to jump up to 14-71... More air with less heat. I'd guess you would probably only have to replace the blowers themselves (rather than carbs, linkages manifolds, etc).

Good suggestions! I especially like Sydwayz and THLWL's.

Tommy- You forgot to mention using the money for a 10% down on a pool like yours!! Jo would say that's more important. What an awesome pool!

The blowers are slightly overdriven and make about 4-5#. I could overdrive more and agree that intercoolers are a good idea. 14-71's would be great, but that means going to larger dominator-style carbs.

There may be enough $$ to replace the heads: was thinking about BMF 385cc. Any thoughts about them?

Due

I can't say that heads would make any more power.

You'll find that boost could decrease with more flow. What I'm trying to say is, in order to make more power you need more oxygen. if you free up the flow at the heads but leave the blower alone, you'll net the same power. you really need more air flow from the start to the finish to make more power, but you are looking in the middle. So... heads are a good plan only in conjunction with more flow before it too.

780 seems a little soft for that setup. You could easily expect 650 plus with N/A 572's on a single 1050. 5 psi should be netting you better than 110-120 hp.

I'd agree intercoolers would be the way to go. Before I went with a larger Roots, I'd look at Whipples & coolers w/efi. Kind of a budget-buster though. I'd consider something like the J&S ignition that would allow you to safely get more aggressive with ignition advance.