I decided to spend some more time today to finish up the LQ4 tear down.  I was having issues being able to get the crank bolt off, even with my 350 ft lb electric impact wrench.  So I had to end up putting the flexplate back on to lock the crank into place.  Breaker bar and a little muscle later it was off so I pulled the flex plate back off.  Went to pull the crank pulley off and remembered just how much the HFT 3 arm pullers sucked.  Went to Advance Auto and rented the nice jawed puller they have that I used when I did my cam swap.  Of course I had jumped the gun by pulling the flexplate off again since the puller was spinning the crank so I once again installed the plate.  Couple minutes later the pulley was off and I went to down on breaking it all down.  Couple hours later I ended up with a nice bare block ready to be re-molded into a nice power plant for the future.

And on a plus note for the build, I received the first on a long list of parts that will end up going into the build.  A set of Brian Tooley Racing Slow Leakdown Rate lifters.  Let the pile of parts begin!

For around the last week or so I’ve been having some troubles with the bird occasionally having somewhat violent misses in the motor.  I spent a few days trying to track down any vacuum leaks or other issues that I might have caused when I recently put the gauge pod back in.  After a few days it then began to throw a code for low circuit on the MAP sensor.  While it was plausible that I had done something during all the electrical work to bork up the sensor wires but I was doubting that.  My money was on the fact that when I replaced all the top end sensors in March of last year while doing a lot of cleanup and de-greasing, I had poorly chosen to use a cheaper unit instead of authentic AC Delco or GM pieces.  And here is something to back up that belief.

First of all I hate how you have to pull the entire intake off just to get at the MAP sensor on these cars.  It really shouldn’t take an hour and a half just to swap a sensor.  After pulling the intake I tried to pop the existing MAP out and while trying to pull it out of the intake it simply came apart.  The top and bottom pieces separated so I was left staring at the guts of the sensor.  Then as I tried to pull the plug out of the intake it just started breaking into pieces.  This is what I was left with.

Fortunately I had recently picked up a complete motor from a truck that I plan on rebuilding and it still had it’s MAP sensor.  Now the truck sensor is a bit different physically than the car version and in it’s stock form would not fit on the LS6 intake.  On the left is the LS1/LS6 style with the truck version on the right.

So I took some snips and cut off the retaining clips on one side and then filed it down to the sensor body.

Afterwards it popped right into place.  After getting everything else re-installed I went cruising around to put some miles on it and after about 50 miles in various traffic conditions it gave me not a single problem.  And that is why from this point on I won’t be using anything other than official sensor parts.  On a side note I had my scan tool hooked up while driving around and noticed that my LTFT on both banks are reading around +20 – +22 so the system is just dumping fuel and in all likelihood destroying my O2 sensors.  I’ll have to tend to that in the very near future unless I want to replace even more expensive sensors soon.

So last weekend a great offer popped up on a local facebook page for a complete LQ4 engine.  Not the precise one I was looking for but since it uses the same block as the LQ9, it really didn’t matter that much except the LQ9 comes with better heads.  After some back and forth haggling we came to a price and on tuesday evening he swung by and dropped it off.  Here is the new base for the future powerplant upgrade for the bird.  A 6.0L LQ4 from a wrecked 05 Silverado 2500.  When the seller said it was a complete engine I expected a longblock with intake or something of the sort.  Instead he gave me something that looks like the hulk just ripped it straight from the truck.

So after work today I did a few things in the yard then decided that I wanted to get a little work done on the tear down so that I can start parting out all the pieces to make back some of the base cost.  After a little sync work between the stand and hoist I got it successfully transferred over.

I then spent the next several hours tearing into it and getting everything off.  This motor was a mess.  It had gunk and dirt eeeeverywhere and build up so thick I had to dig around with a screwdriver just to find some of the head bolts.  It also had some pretty significant internal oil leaks with a few of the center bolts on each head coming out completely coated.  Although I don’t know if that was a prior issue or a cause of the impact loosening some gaskets and letting oil by.  Although I am leaning toward pre-existing condition due to the large amount of oil that was in the intake along with the massive carbon buildup in the head runners, chambers and all over the pistons.  There was so much build up that when I pulled the old head gasket the carbon stuck out over the cylinder like a shelf.  Everything looked good after pulling the heads except for 2 cylinders which had some rust and what felt like scoring on the cylinder walls.  I am hoping that they won’t be an issue when having it machined.  The only real things left in there is the rotating assembly, camshaft and some sensors.

I will probably have the block bored out to 4.030 and put in a 4″ stroke crank to make it a 408.  If that won’t be enough power for a daily driven toy then there really is no hope for me.