I'm no expert, but most definately you're going to have to strengthen the bottom end with twin turbos. That's if you want to make real power and run boost above 8 or so pounds. I would like to think with two turbos you want to make some brute power and a stock end wouldn't hold up. So, you'll need a forged rotating assembly. Without a forged bottom end, 10-12 pounds will be too much boost on a stock crank, rods, etc. Also, if you can get a good price on the heads sell them, make sure you lower your compression ratio with the right pistons as well. Sounds like it'll be a sweet setup.
