In my 20+ years of playing with engines, I have never seen a crankshaft fail like this. Needless to say, my confidence in this, or any other M96 engine had (has) been reduced to null.
Never fear, Captain America to the rescue!
THE PLAN:
After getting a quote of $4500 for a replacement crankshaft, I gave up all hope on putting this M96 back together. Instead, I set out on an ambitious mission to replace the original M96 with a Chevrolet LS based small block for the similar budget of a junk yard (aka: let's roll the dice and see how long THIS one last before something else catastrophically lunches itself) replacement engine... which is between $3500 and $4000.
STEP 1 - FIND AN ENGINE
With the help of my trusty side-kick, I located an all aluminum 5.3L V8 from a 2006 Chevy Silverado called the L33. What makes this motor special is that it shares the same head castings as the coveted LS6 motor that was used in the first (C5) Z06 Corvettes. However, most junk yards don't realize this, so I was able to grab a complete 120,000 mile running drop out for $700. This came with all the wiring and ECUs I needed to fire the engine up.
STEP 2 - BUY THE ADAPTERS
This was a painful part of the process. The adapter "kit" I bought was by far the most expensive part of the entire process (cost more than the car itself!) This was even after I opted to not buy the optional items like an upgraded clutch, eater pump and electric power steering pump. I was rightfully convinced that I could source and / or engineer more cost effective alternatives myself.
As I said in the preface above, I should have just bought the engine adapter and flywheel directly from Kennedy and fabricated my own motor mounts. While the components that were included in my kit were very pretty and powder coated... I didn't bother using half of the pieces, and the other half were mostly overkill.
STEP 3 - PREPARE THE ENGINE
In truck form, the L33 was simply never going to fit. The oil pan was too deep, and the intake was too tall. The oil pan, pickup and dipstick were replaced with a new factory original setup for the F-body LS1. The intake manifold was replaced with an aftermarket Chinese (Qualifier, I think) aluminum piece.
Next, the crank pulley and accessories needed be addressed. When I say it's tight in the front of this engine setup... IT'S FRICKING TIGHT! The only way to make this work is to use the pulley from a front wheel drive LS motor (LS4) found in vertain Grand Prix GXP or Imapala SS (the bull**************** Impala SS, not those sweet Impalas from 1994 - 1996 that I spent many formidable years growing up in after graduation).
Before anyone starts talking about using the water pump or accessory drives from this engine in addition to the pulley, they won't fit. Plain and simple, nothing is going to fit above the center line of the crankshaft. This is the only way to run accessories off the front of the engine in this configuration while keeping any semblance of a stock appearing firewall.
I warned you that it's tight:
