He is telling me that i wont have any luck using a dart aluminum block ( WHICH I ALREADY HAVE) on blown alcohol or any other aluminum block in this application. He says the mains will have to be redone quite often depending on how much you run it. He is trying to sell me his complete motor that has the motown steel block and says no problem with the mains staying put. IS THERE A POWER LEVEL THAT THE ALUMINUM BLOCK WILL HAVE MAIN PROBLEMS AND AT WHAT HP LEVEL WOULD THAT BE AROUND? I only need around 900 or so and its going in a boat where you really never get a solid bite like on a racetrack. What do yall think? Will it hold u p or not?