I'm going to throw something else out there.
If youre going inline 6. Look into the Vortec 4200.
In stock form it produces over 100 Hp more than you'll get out of any built up inline 6. They have a flat torque curve that starts at about 1500 RPM and goes up to over 5000 RPM. Not too shabby in my book.
Swapping them out, doesn't require any more than doing a LS 5.3 swap.
There's plenty 2002-2009 Trailblazers, Envoys, Bravadas, and Rainiers in the junk yard with good running engines.
If you rebuild the engine, moneywise, it's equivilent to the early engines.
I have an 09 apart in my garage right now, I'm amazed at how simple it is.
Not to mention it weighs probably 300 lbs less than a 292.
http://www.vortec4200.com/forum1/vie...php?f=10&t=821