building a 2011 6.0
projected 1100 horsepower
what is the best transmission to use?
its going in a 2013 silverado and i know the 6L80 wont handle it

 

I'd call TCI or a reputable transmission builder. Many people build 4L80E trans that hold big power. Powerglide if your building a drag specific truck. You should give a description of your truck besides the power and your ultimate use and goals.

 

4L80e

TH400 if you don't mind not having OD

 

Check out http://www.jakesperformance.com/4l80/
Jake supplied all my T400 parts years ago, I stopped building them a few years ago. I had no time with life getting in the way
Jake's a good guy

 

you dont need to go crazy for 1100 wheel hp. 300m input shaft, sonnax extreme duty billet fwd clutch hub, 6 friction and dual fed direct clutch, 300m billet main shaft. There are a few pump mods to keep it alive at the pressures you'll need to hold that power. PM me if you want more info. I build 4L80e's and Th400's for a living.