My DIY LS7 Headswap
 

C6 Z06 Head Swap DIY
By JeffreyStar

Tools Needed:
20° Offset & 45° Angle Long Reach Needle Pliers
Standard Metric Tool Set
Big ass ½” breaker bar
Quality electric impact
Swivels
Metric Gear Wrenches
Inch Pounds Torque Wrench
Foot Pounds Torque Wrench
Jack & Jack Stands and Ramps (my preference)
Electric Impact
Various length extensions
Various Screw Drivers
Oil Catch Pan
Grinder or access to one
Wet/Dry Vac


Parts Needed:
GM MLS Head Gaskets
GM LS7 Headbolts
GM LSX Cross-over Pipe plugs
Roll of painters tape
Duct Tape
Your favorite paint polish
Your favorite Wax
Large Cotton Towel
A box of Ziploc bags
Oil & Filter for change
Dex-Cool Mix or Dex-Cool & Distilled Water
Big Thick 7-11 Straws
Black & Red Sharpie
Shop towels
Nitrile Gloves



1) Protect the Paint:

Expect to use a complete roll of painters tape to carefully tape up the fenders, hood edge and the top of the head light enclosures. During this job you will drop tools on your car and you will be very glad that you protected your paint. I covered everything up down to the edges of the fenders all the way back past the cowl because tape is cheap and paintwork is not.


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2) Elevate Car & Remove Engine Covers, Unplug EVAP & Brake Booster Hoses:

The car needs to be high enough to get under it easily to loosen exhaust & drain oil etc.
With a COLD motor and the car in the position that you will be working on it, hood up, windows down, music OFF, garage fans OFF, start the motor and listen to what it sounds like. Watch the oil pressure for your car when it is cold. Note all of the noises, idle rpm and pressures. Mentally note this experience for later.
Unplug the Brake Booster Hose
Disconnect the green EVAP soft line from the hardline against the firewall
Remove Engine Covers

3) Disconnect Positive Battery Cable:

Roll your windows down, Pop the hatch, open the battery cover and use a long10mm socket with a long extension to remove the terminal retainer, wiggle it back and forth and pull upwards. I wrapped the positive cable in an extra microfiber towel and sit away from the positive terminal. Now place a towel over the back of the hatch to keep it from latching with out power. Lower it slowly.

4) Drain Coolant

Remove the coolant pressure cap
Place a drain pan under the drain cock
Use the 20-degree long pliers to carefully loosen the radiator drain peacock valve until there is a steady flow of coolant out of the peacock valve.
We want to drain the radiator to about halfway full, we don’t need it bone dry so about 3 gallons is more than enough, now close the peacock by hand, if you use the tool it is plastic and you will likely crack it. ☺ Keep in mind that antifreeze is dangerous, contain or dispose of it carefully and never leave it out in a bucket if you have dogs or cats it tastes like Kool-Aid and they will kill themselves drinking it in seconds!!!!


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5) Remove Air Intake / MAF System

Remove the whole thing and Ziploc bag any loose pieces and label the bag ‘air-intake’ parts.

6) Remove Generator/Alternator

Remove serpentine belt
Unplug single weatherpack connector from the top of the alternator
Remove positive terminal by removing 13mm fastener from back of the alternator
Put 13mm nut back on alternator for safe keeping
Remove both 15mm bolts and remove alternator
Ziploc bag the 2x15mm bolts and label ‘Alternator’ bolts


7) Remove Radiator Hoses & Fans

Remove Upper Radiator Hose from car
Disconnect Coolant bleed pipe hose from TB, Coolant Tank, zip tie back out of the way near the passenger side of the engine bay
Remove reservoir feed hose and zip tie back out of the way near the passenger side of the engine bay
Remove upper fan shroud retainer (4 10mm bolts)
Remove all wiring clips, hose clips and anything connecting to the fan shroud
From UNDER the car:
Unplug the large fan weather pack connector that powers the fans (bottom right corner)
Remove 2 10mm nuts holding the fans to the radiator assembly (bottom left corner & top right corner)
Remove fans via the top, careful not to hang the fans up on anything (a friend is helpful here)
Ziploc bag all the bolts and label ‘Radiator / Fan bolts’

8) Clear Movement for the ASM/ABS Module

From UNDER the car:
Locate the ASM/ABS mounting bracket
Locate the ASM/ABS mounting bracket attachment points to the subframe facing forward near bottom
Remove 2 13mm bolts
With the fans removed and the ASM/ABS Module loose we have room to remove the Power Steering Pump and Generator Bracket
Ziploc bag the bolts and label ‘ABS Module bolts’

9)Liberate the Power Steering Pump Assembly (we aren’t removing it, just giving ourselves room to move it forward)

First let me say this is a step that you need patience. If you feel you are getting frustrated take a break and come back to this step. It is a royal PITA but once you’re done you’ve done most of the grunt work and it will be time to make REAL HEADWAY! ☺

Spin the Power Steering Pump and visually locate 3 of the 4x13mm of it’s fasteners, the 4th is difficult to see but it is at the lowest point and you can feel for it with your fingers and easily locate it.
There is a PS sub-bracket that 2 of the shorter 13mm bolts attach too, there are 2 longer bolts that are at the very top and bottom of the sub-bracket that actually go through onto the generator bracket which we must remove to get access to the generator bracket.
They should be the very bottom and very top bolts. You will need to spin the pulley to gain access to the bolts. I used my mini-electric impact and a combination of swivels and extensions to gain access to back these out but you can just use a ratchet. Once the PS pump is loose from the Generator bracket you need to slide the PS fluid reservoir straight UP off the bracket. BINGO full access to the Generator Bracket. No need to remove the lines or pull the pump out of the car etc. Just push it forward, we are ONLY swapping the heads in this DIY.
Ziploc bag the bolts and label ‘Power Steering Bolts’

10)Remove Alternator Bracket

Locate 4x15mm Fasteners holding the bracket on the LS7 motor.
Remove all 4
Remove Alternator Bracket from engine bay
Ziploc bag the bolts and label ‘Alt Bracket Bolts’


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11)Remove Coil Pack Assembly

Unplug the white Coil Pack connectors
Unplug all Sparkplug wires from the Sparkplug; leave the wire attached to the coil pack
Remove all 10mm Coil Pack fasteners
Remove Coil Packs from engine bay
Ziploc bag the bolts and label ‘Coil Pack Bolts’


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12)Remove Headers or Manifolds (AHR LT Header Specific)

From UNDER the car
Remove collector bolts (2x14mm nuts/bolts)
Either unplug or provide room for O2 sensor harness to move
Remove header bolts and set gaskets aside, nothing orientation so they can be reused
Carefully lay headers out of the way but you can leave them in the engine bay my ARH had enough play/room to stay there during this entire process.
Ziploc bag the bolts and label ‘Header bolts’

13)Intake Manifold Removal Process

Remove 15mm bolt holding harness from Passenger side cylinderhead at the rear, finger thread back into head safekeeping
Remove 15mm bolt holding harness from Passenger side cylinderhead at the front, finger thread back into head for safekeeping
Unhook the ECT harness from the Driver side cylinderhead
Note all of the plastic hardlines have quick disconnect fasteners. Disconnect them carefully by hand, a simple small flat head required if anything and no force is needed. Very difficult to describe these connections but look at them and take your time until you understand how they come apart. Very simple.
Unhook the two PVC hardlines from oil reservoir tank
Unhook the two PVC hardlines from the valve covers
Remove Rubber PVC hose at the lower TB
Unhook and back-route the entire wiring harness from both side of the motor including the plastic retainers at the fuel rail
Back-route the alternator cable
Remove the hardlines that go over the TB they connect at the lower right side of the TB -> Follow the hardline to the back of the manifold where there is another quick disconnect fastener. Remove.
Disconnect the fuel line from the fuel rail with a quick disconnect tool
Turn the fuel feed line to 12 o’clock and put your finger on the open fuel rail
Plug fuel rail with a rubber hose or vacuum cap OR just allow to drain in a cup but later it will be a mess if you don’t plug it up now.
Turn the fuel feed line downward and drain into a cup, assuming your cup was clean pour it back in your tank it’s probably worth $.050 ☺
Use the below diagram to crack loose all of the 8mm bolts in reverse order counting down from 10 to 1
Use ¼ Ratchet or 8mm gear wrench to completely loosen the rear bolts
Use some of your painters tape to tape the bolt in the highest “up” position so you can clear the heads when you remove the manifold
Remove the other 8mm manifold bolts (bag them!)
Elevate the manifold, move forward 3 inches, grab a flash light and look behind it near the firewall
Locate the Brake Booster hose and emissions rubber line, free them from any retaining clips
Visualize how you will pull forward and rotate counter clockwise the manifold to get the hoses clear of the oil pressure sensor
Now lay a big beach towel under the manifold and over cylinder heads (this will save your intake seals from getting torn!)
Remove the manifold from the car carefully
Remove the Coolant Air Bleed Pipe from the cylinder heads
Ziploc bag the bolts manifold bolts and label ‘Manifold Bolts’
Ziploc bag the Coolant Air Bleed Pipe and pipe and label ‘Bleed-pipe bolts’



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14)Remove Rockers, Pushrod and Valve Lash Caps

Remove the valve covers bolts (4x10mm)
Remove passenger side valve cover (no need to mark they have an orientation that can’t be screwed up, oil fill always goes on passenger side)
Remove 2 8mm rocker arm bolts and STOP
Cut out two 2’x2’ or close pieces of cardboard
Near one edge of the cardboard mark off 1-3-5-7 with ample room between the numbers
Near one edge of the cardboard mark off 2-4-6-8 with ample room between the numbers
Grab a drill bit that is about the same thickness as the pushrod and another that is same thickness as the rocker bolt
Drill two pushrod holes above each number
Drill two rocker bolt holes below each number
Remove all 16 pushrods and rockers retaining the proper order and orientation of everything
Using a magnet remove all eight Intake Valve Lash Caps and bag them….you guessed it in a Ziploc bag and label it! ☺
Sit everything aside in a safe place where it won’t be disturbed by you, your dogs etc. ☺


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15)Remove the Cylinder Heads!

Crack Loose the 10mm and 15mm heads in reverse order starting from 15 – 1
Put towel down between the block and header to catch the coolant that will spill
Grab your wet/dry vacuum and get it ready to go
Remove bolts in any order now that they are loose but 15-1 is ideal
Extra person manning the Wet/Dry vacuum is a total plus here
Grab the Cylinderhead and remove it, sometimes they need a little mechanical help with a small pry bar
Vacuum Coolant from the cylinder bores immediately then the rest of the liquid
Remove the Headgasket if it is stuck to the block
Toss the old bolts aside but save one of each 10mm and 15mm for our next step, clean up!


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16) Clean the Decks

The factory MLS gasket leaves a lot of graphite and sludge and we MUST get 99% of this stuff off the block. This will take time, this will take your own personal judgment, is it as clean as it needs to be to seal? Not sure, keep cleaning. Is it simply bare metal with tiny none removable impressions of graphite well then we are ready to move on to step 14. Here were my steps:

1) Flat razorblade to carefully scrape the entire surface is clean as possible
2) Wet/Dry Vac the area I’m working
3) 1500 grit sand paper in right hand, Wet/Dry vacuum attachment in the left, sand and vacuum together as to not allow any debris to fall into the motor

This got my block deck area to a near spotless condition.

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17) Evacuate fluid & debris from the head boltholes

Multiple Options to get all of the fluid out of the bolt holes here is mine:
Wet/Dry Hose Attachment + 7-11 Style Thick Straw + Duct Tape = GREAT tool to clean out the head bolt holes
OR you can use Rolled-Up shot towels or Compressed air (never done that method)
You MUST get ALL of the liquid out of ALL 15 head boltholes so look in them with a flashlight often.

Take an old head bolt and grind off a straight line with your grinder to create a channel that will catch and help you remove the old factory Loctite crud. Really this “tool” is no different than a handmade tap but it won’t cut any of the threads.

It will look something like this:


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Hand thread the bolt into the bolt hole, then run the bolt down the hole with your electric impact on the lowest setting. I used a pattern of 10% deep, back out clean, 30% deep, back out and clean, etc. I used the vacuum attachment I made with a thick 7-11 Straw & Duct Tape to remove any debris that did not come out on the bolt. When you think you’re done get a flashlight and look down into the bolthole. I’ve heard of people striping head bolts out that they thought were clean, again just take your time here and get it right. If you think its right, ask your buddy to look and give you a second opinion. Clean is Clean.

18) Transfer Head hardware

Inspect new heads for steam hole freeze plugs; if they do not have them you have two choices:
1) Transfer the old freeze plugs to the new head
2) Purchase and install GM part # 12602540 to the rear of each head once you’ve decided your orientation (the heads are the same so you can use them on either side of the motor but you need to pick an orientation now so you can install the freeze plugs/steam pipe plugs if needed & other hardware.
Install all 8 Intake valve lash caps on the Intake valves if required (Check with your head supplier or instructions if this is needed)
Transfer the Coolant temperature sensor to the new driver side head
Transfer the Coolant temperature sensor plug to the new passenger side head
Transfer the rear harness 15mm fastener & front harness 15mm fastener by just a few threads so they are in a safe place.
Transfer or install new Sparkplugs


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19) Final Surface Prep, MLS headgasket Inspection & Initial Assembly

Put on nitrile gloves because you don’t want skin oil on any of these surfaces before they are mated
Locate your MLS headgaskets, open them and clean them with the Wet/Dry vacuum of any paper particle or otherwise from the packaging
Note they have an orientation that is clearly marked FRONT and they have a tab that has a 7.0. Easy huh?
Start with the passenger side and:
Using a freshly washed quality microfiber or cotton towel and a bottle of rubbing alcohol we will wet the towel and thoroughly wipe down:
1) The Passenger side Block’s entire sealing surface area
2) Both sides of the headgasket then lay then carefully lay headgasket on the block correctly
3) The Passenger side cylinderhead then slowly place it into the dowels/on the block and hand thread 2x10mm and 2x15mm headbolts to secure it.

20) SANITY CHECK

Time to triple check:
Cylinder Head orientation
Steam Plugs orientation
Gasket Orientation

21) Fasten the headbolts

Ratchet tighten all 15 head bolts stop as soon as you feel any resistance.
Torque all 15mm M11 cylinder headbolts down to 22ft lbs. in the order shown in the diagram 1-10.
Back all 15mm M11 cylinder headbolts out 1 full turn in reverse order shown in the diagram 10-1.
Torque all 15mm M11 cylinder headbolts down to 22ft lbs. in the order shown in the diagram 1-10.
(in lieu of an Angle meter which I’ve never used)

http://buy1.snapon.com/catalog/item....store&tool=all

Mark the 12 o’clock position on all 10 M11 cylinder head bolts using a black sharpie., draw the line as straight as possible from the center of the bolt to the 12’oclock position edge.
GET A BUDDY to HELP on the next two steps
Using 1/2” drive breaker bar and a 6-point 15mm socket turn the 15mm M11 cylinder headbolts 90 degrees in the order shown in the diagram 1-10.
Using 1/2” drive breaker bar and a 6-point 15mm socket turn the 15mm M11 cylinder headbolts 75 degrees in the order shown in the diagram 1-10. (I went 75 vs 70 to error on the side of caution)
Torque all 10mm M8 cylinder headbolts down to 22ft lbs. in the order shown in the diagram 11-15.
The process and torque order is the same for both sides.
Awesome you are halfway done with your head swap!


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22) Re-install the Headers

Hand-tighten 10 threads on the first and last bolt with gasket in place, be careful not to damage it!
Hand-tighten the rest of the bolts by the first 10 threads.
FROM UNDER THE CAR
Re-connect and re-fasten the O2 harnesses, verify they aren’t going to melt on the headers.
Line up the collectors and install the fasteners but do not tighten.
BACK TO THE ENGINE BAY
Tighten the header bolts from the center out in two passes.
FROM UNDER THE CAR
Tighten the header collector bolts and double check the wiring is safely reconnected and not going to burn when the car runs.

23-A) Re-install the Valve-Train: BASIC

Install the Intake side valve lash caps if needed (check with vendor if you’re not sure)
Make sure the valve train is clean of any debris.
Open a bottle of Mobil1 and use the cap as a cup, fill it with oil: Lightly re-oil the push rods and re-insert them in the position & orientation that they came out.
Use the Mobile1 oil cap to liberally lubricate the top of each valve and spring.
Install each rocker and hand-tighten each rocker down snug while assuring the rocker tips are lined up with the valve stems correctly.
Torque all rockers down to 22ftlbs. OR USE THE OFFICIAL GM PROCEDURE in section 23-B
Use the Mobile1 oil cap to liberally lubricate the rockers.
Reinstall the valve covers and torque the 4 bolts to 106 inch lbs.


23-B) Re-install the Valve-Train: ADVANCED

1) Install the rocker arms and bolts, Ensure the pushrods seat properly to the ends of the rocker arms, Lubricate Everything.

2) Rotate the crankshaft until number one piston is at top dead center of compression stroke.

In this position, cylinder number one rocker arms will be off lobe lift, and the crankshaft
sprocket key will be at the 1:30 position.

The camshaft and crankshaft sprocket alignment
marks will be in the 12 o'clock positions.

If viewing from the rear of the engine, the
additional crankshaft pilot hole, non-threaded, will be in the 10:30 position.

The engine firing order is 1, 8, 7, 2, 6, 5, 4, 3.

Cylinders 1, 3, 5 and 7 are left bank.
Cylinders 2, 4, 6, and 8 are right bank.

3. With the engine in the number one firing position, tighten the following valve rocker arm bolts:
Tighten exhaust valve rocker arm bolts 1, 2, 7, and 8 to 30 N·m (22 lb ft).
Tighten intake valve rocker arm bolts 1, 3, 4, and 5 to 30 N·m (22 lb ft).

4. Rotate the crankshaft 360 degrees.

5. Tighten the following valve rocker arm bolts:
Tighten exhaust valve rocker arm bolts 3, 4, 5, and 6 to 30 N·m (22 lb ft).
Tighten intake valve rocker arm bolts 2, 6, 7, and 8 to 30 N·m (22 lb ft).

24) Re-install the Intake Manifold

Install the Coolant Air Bleed Pipe and torque bolts to 106lb inches.
Clean, degrease, vacuum all debris from the manifold’s many small nooks & crannies.
Wipe down the manifold gaskets with rubbing alcohol.
Wipe down the entire mating surface on the cylinder heads with rubbing alcohol.
Tape up the two rear 8mm bolts in position 8 & 9 so that they are not protruding from the bottom of their bores.
Visualize how you will swing the manifold into place in a Clockwise-backwards motion (a buddy is very helpful here) carefully watching and clearing the brake booster hose & evap line hose (it is good to tape them together I found out). As the manifold moves into place connect the oil-pressure sending unit.
Verify the manifold is lined up and seated correctly by looking down the manifold bores to assure 99% alignment.
Remove the tape from the bolts in 8 & 9 position and drop them into place and get them started with 2-3 turns into their respective bores.
Install 8 remaining manifold bolts and finger tighten all of them by a few threads.
Hook up the lower PVC rubber hose (it does not have a fastener)
Torque the manifold bolts down to 44lbs inches in the sequence shown in the diagram.
Torque the manifold bolts down to 89lbs inches in the sequence shown in the diagram.
Re-install the TB hardlines and reconnect them to the TB & the hardline at the firewall.
Re-route the Alternator cable back under the fuel rail like it was from the factory, leave facing the front of the motor, awaiting the alternator installation.
Re-route and re-connect the wiring harness back in place carefully and methodically, double-check everything.
Re-Connect the ECT harness.
Re-install the PVC hardlines from the reservoir tank to the valve covers.
Hook up the EVAP hardline and Brake booster hose.
Connect the fuel line and re-install the fuel line retainer clip.
Re-Fasten the 15mm bolts in front and back of the passenger side cylinder head so that they hold their respective harnesses in place correctly as before.


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25) Reinstall Coil Pack Assembly

Lay the Coil Packs back in place
Finger tighten all 10mm coil pack fasteners to hold it in place
Re-connect all Sparkplug wires
We will be removing the Valve Covers to re-torque the rocker arms after our first heat cycle.

26) Reinstall Generator Bracket

Load the bracket back in position by swinging the PS pump out of the way.
Tighten all 4 15mm bolts to 37ft. lbs. or 2 mini-grunts as they say ☺


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27) Reinstall the Power Steering Pump Assembly

Spin the Power Steering Pump and visually locate 3 of the 4x13mm of it’s fasteners, the 4th is difficult to see but it is at the lowest point and you can feel for it with your fingers and easily locate it.
There is a PS sub-bracket that 2 of the shorter 13mm bolts attach too, there are 2 longer bolts that are at the very top and bottom of the sub-bracket that actually go through onto the generator bracket which we must remove to get access to the generator bracket.
They should be the bottom and top bolts. You will need to spin the pulley to gain access to the bolts. I used my mini-electric impact and a combination of swivels and extensions to gain access to tighten these once I had hand started all of them and turned them several threads.
Tighten 2 13mm bolts to 37ft. lbs. or 2 mini-grunts as they say ☺

28) Re-install ASM/ABS Module mounting bolts.

From UNDER the car:
Locate the ASM/ABS mounting bracket
Locate the ASM/ABS mounting bracket attachment points to the subframe facing forward near bottom
Re-install 2 15mm bolts

29) Re-install Radiator Hoses & Fans

From UNDER the car:
Load the fans into position correctly, nearly impossible to describe and so easy to do. ☺ Take your time they only go one way.
Plug in the large fan weather pack connector that power the fans (bottom right corner)
Re-install the 2 10mm nuts holding the fan to the radiator assembly (bottom left corner & top right corner)
Re-install the upper fan shroud retainer (4 10mm bolts)
Re-install all radiator hoses and push them into their appropriate retainers
*The PS pump hardline goes under these)
*Great time to pre-fill the radiator with a 30/70 mix of Dexcool & Distilled Water through the upper radiator hose before it is reconnect to the motor.

30) Re-Install Alternator

Lay the alternator into position
Fasten it down with both 15mm bolts
Hook up the single weather pack connector
Re-route and the alternator feed back to the positive terminal on the back and tighten the 13mm nut down snug.
Re-install the serpentine belt


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31) Re-install the Air Intake / MAF System

Install the whole assembly and plug everything in correctly.
Hook the battery back up, OMG so exciting! ☺


32) Pre-START CHECK LIST

Check every connector, harness, hardline, fuel line, vacuum line, bolt, nuts, etc etc.
Make sure nothing is laying on the header
Clear the engine bay of every tool you’ve used
Have someone else give everything a once over just make sure you didn’t miss anything! ☺

33) Test-START

Start LS7 and watch oil pressure, listen for strange noises, hissing, anything that doesn’t sound normal kill the engine immediately and investigate.
The LS7 is a little noisy at start up so give it 2-5 seconds before deciding to kill it unless you hear something awful.
It will immediately start to smoke as it burns the oils off the heads and headers this is normal.
After 20 seconds or so turn the motor off and move on to the coolant fill procedure.

34) Coolant Fill Procedure

Remove the coolant pressure cap.
Fill the coolant reservoir tank with the appropriate mix of Dex-Cool and distilled water
Start the engine and allow to idle for 4 minutes while watching the reservoir tank keep it filled as the LS7 warms up.
Run the engine between 2000-2500 RPM for 2 minutes while adding Dex-Cool mix to the reservoir tank as needed.
Install the coolant pressure cap
Allow the engine to idle until the oil temp reaches at least 100 degrees but preferably.


35) Final Sequence

Allow LS7 to fully cool down.
While the LS7 is cooling off, remove all the painter tape, polish off the adhesive and apply some wax to those areas.
Change oil.
Re-tighten Header Bolts from the inside out.
Remove Coil-Packs
Remove Valve Covers
Visually inspect valve train for proper alignment.
Check torque on all Rockers at 22ft lbs.
Re-install Valve Covers
Re-install Coil-Packs
Re-install Engine Cover Plastic
DONE Enjoy!!!!


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PS: Special thanks to LS1Howto.com's JMX and any other people who provided me images and data to get this process completed.

If you see any errors or would like to contribute/add to my post please PM me or post it up! I'd love for a few different people to go through this document and provide feedback, notes and additional pictures to help the community in a positive way. Thanks!

I am not perfect and this is just my effort to help others. If you follow these instructions and something goes wrong I am sorry but I am not responsible. Use at your own risk! :)


UPDATE:

Here are the before and after dyno results:


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Great write up :thumbs: im sure forum will be using this for years to come

HOW LONG DID IT TAKE FROM START TO FINISH?

Great job!! Thank you for taking the time to put this together

:thumbs: Good job! Very well done.

Great write up!! Thanks!! :cheers:

Yea this is over my head lol

:rofl:

Back when I was a kid...all day long. Now that I'm older and I make a good living...I'm clearly gonna pay somone to do this sh*t if and when I pull the trigger. :lol:

awesome write up!

Definitely a ton of work and great write-up.

STICKY !!!!

:cheers:
DH

Thank you for the write up...I am in the middle of a head swap. Do you have to turn the number one cylinder to TDC when putting the rocker arms back together?
Thanks

Great job! Thanks.

I have always gone with the "tighten to 22ft lbs" and go process, which all my engine builder references & trusted tuners seem to be OK with...however I've updated the thread with the official GM procedure feel free to use that process if it will help you sleep better at night. To each their own! :)

Awesome write up! Thanks for taking the time to document everything.

As someone mentioned, I'm wondering how long it took you to perform this?

I have a feeling this would take me an entire season. :lol:

Awesome procedure Jeffreystar. Well done.

This job is really no big deal. Just look at it in sections. Take one step at a time and anyone can do it. It took me 3 hours to remove the heads. Three hours to clean the deck surface and remove the water from the bolt holes, then around 5 hours to install the heads. Can easily do this on a weekend.

The only part that I read that makes me nervous is the sand paper on the deck. I think even with a shop vac you are risking tiny sand particles to get down in the water jacks and work there way to the pump, or worse, get trapped in the inner skirt of the piston ring.

I read where some guys were using scotch bright to clean the pistons and even the fine fibers of it would get trapped in the top of the ring. One suggestion was to rotate the engine so the piston was at the bottom, put a VERY light coat of oil on the cylinder wall with your hand then rotate the piston back up and down then wipe off the cylinder with a towel where any particles could be trapped in the oil film.

Of course I would also use an air gun to blow out all the holes and around the pistons at TDC, just my .02 cents. Great write up!

Awesome write up!!! :cheers:

Best write up ever on this forum!

This job took me 8 total hours of labor, broken up over 4 days. Vengeance Racing provided me a core exchange on my heads so my car didn't have to be down.

Good suggestion regarding the oiling of the cylinder walls, thanks for your contribution. You can never be too careful.

Compressed air is usually a bad idea I stick to pulling dirt/particles and water/coolant off the motor with the Wet/Dry Vac. Forcing the particles deeper into the hole, crevasse or piston ring/cylinder wall is usually what happens when you go nuts with compressed air. However, I'm accident prone and I usually get something flung into my eye so maybe that is also why I don't like it? :)

I'm up to 7 LSX heads/cam installs and close to 8+ LTX/LC2/302 heads and cam swaps lifetime and I've always done it this way and always used this step.

There are always different ways to clean the deck but using a bit of 1500 as a FINAL PASS to get any remaining graphite off the deck while simultaneously using a wet/try vac to catch anything large from falling into the motor works just fine.

After one heat cycle, we change the oil & filter on the LSX swap as noted.