I ran my 468 BBC on the dyno with a 1000 Drag Race Demon and then we bolted on a 1000 Holley HP and pulled the engine again. The Holley made 3-4 more hp across the curve but lost 5-6 torque across the curve compared to the Demon. My brother in laws 461 BBC dynoed his with his 850 demon and then he bolted on the 1000 Holley HP. The Holley made 4-5 more on the toque and 11 hp more than his Demon. I hope your Pro Systems carb works out for you.