Cadillac Owners Forum banner

Heads Cam Intake Throttle Body Install Writeup

30993 Views 36 Replies 11 Participants Last post by  soopervdave
This Heads / Cam / Intake / Throttle Body install writeup is for an LS6 CTS-V 2004 & 2005. LS2 CTS-V’s will be similar and most of this can be used, but some of the part numbers might change. Also, GM part numbers get superseded often, so some of the part numbers will change over time. I’m writing this Sept of 2012.

In the middle of my install my phone decided to be a bitch and quit working, so I lost some of the pics towards the end, but luckily I had downloaded the bulk of them before it decided to die. Anyways…..

Tools you’ll need:

Sockets: 8mm, 10mm, 13mm, 15mm, 18mm, 19mm
24mm socket (Balancer Bolt)
Wrenches: same as above. Gear wrenches help a lot
5/8” Deep Well Spark Plug Socket
Breaker Bar
Torque Wrench (Ft. Lbs)
Torque Wrench (Inch Lbs)
Screwdrivers (Flathead and Phillips)
3 Jaw Pulley (3 Ton)
8mm Allen Wrench/Socket
5 gallon Bucket to catch Coolant
If you use ARP head studs 1/2” Deep 12pt Socket, 3/8” Deep 12pt Socket
3/8” white plastic fuel line removal tool


Heads of Choice (I used AFR 215 massaged by Tony Mamo)
Cam of Choice (I used Comp Cam 227/231 114LSA)
FAST 102 Intake (I used one massaged by Tony Mamo)
TB of Choice (I used Nick Williams 102mm)
LS2 Timing Chain (I used Rollmaster #CS1180)
Pushrods (I used Manton)
Lifters (I used LS7’s)
Melling Oil Pump #10296 w/ optional spring
Yella Terra 6645 LS 1.7 Rockers
Fastenal Bolt (for balancer install) #40768 (M16 -2.0 pitch x 120mm long)
Spark Plug I used good ‘ol AC Delco #
Casper LS6 to LS2 wiring harness adapter
7 quarts 5-30 Mobil 1 / Oil Filter


ARP LS6 Head Stud Kit # 234-4317
Or New OEM stock head bolts #
Head Gaskets # 12498544
Or Aftermarket Head Gaskets of choice (I used Cometic 4.160 Bore .040)
Timing Cover Gasket # 12633904
Front Engine Seal # 12585673
Valve Cover Gaskets # 12560696
Or I used Yella Terra taller valve cover gaskets #YT5132
Balancer Bolt # 12557752
Intake Manifold Gaskets (8)# 12533587
Oil Pump Oring # 12557752 (if you don’t use Melling oil pump / it comes with oring)
Water Pump Gaskets #
Exhaust Manifold Gaskets # (I’ve always used GM gaskets since day one, and never had any problems with them sealing)

Misc Needed:

Blue Loctite
Brakleen (3 cans)
RTV Gasket Maker (black)
(2) Gallons of Dexcool Coolant
Anti-Seize Lubricant


Oil Catch Can (I used Elite Engineering)
(2) New Header to catback gaskets
(2) Knock Sensors # (I didn’t replace mine)
(2) AC Condenser Orings # 25740416 (if you remove condenser)
(12) Header/ Exhaust Manifold Bolts #
LS2 Fuel Rail
Lower Temp T-Stat (I used 160 degree)

Here’s a pic of the Comp Cam, Nick Willaims Throttle Body, Yella Terra Rockers, Rollmaster LS2 Timing Chain, Bosch 36 lb. Injectors, Casper LS6 to LS2 wiring harness adapter….and some Simple Green 

Cathedral Ports (all ported and machined)

AFR Heads:

Yella Terra Rockers:
See less See more
1 - 20 of 37 Posts
FAST 102 (before I painted it silver):

There really isn’t a set way to take everything off. I’ll give you the way I took everything off in order (if my memory serves correctly)

Alright, let’s get started.

Turn the wheels in and remove the inner plastic liners by removing the plastic pins since removing the front bumper is going to happen. Do this before you run your V up on ramps since you can’t turn the wheels after it’s up on ramps.
Here’s a great link for removing your bumper:

We need to get it in the air so we can get underneath it to get the plastic guard covering the radiator, change the oil, remove the coolant, lower the oil pan, etc.

Disconnect the battery.

Drain the oil and remove the oil filter.

Radiator Removal:
Once the plastic guard is off, take the lower radiator hose clamp off and pull the lower radiator hose off until the coolant starts to flow into your 5 gallon bucket, or container. There’s no petcock on the radiator (retarded design) so this is your only option. Empty entirely.
Here’s a pic of the radiator brackets removed (10mm), and the upper radiator hose removed:

The fans can be removed, or lifted out with the radiator. Either way, you need to unplug the electrical connection for the fans, and remove the small pain in the ass Phillips screw along the AC line:

Now, you can either choose to try and bend the A/C condenser out of the way, or remove it like I did. It makes for a TON of extra room. This of course means you would have to get your A/C refilled. If you want to take the condenser out, here’s the two connections:

BTW: Those two AC bracket orings are # 25740416 and they tighten to 48 inch lbs. Don’t over
tighten them and break them like I did the first time.

Remove the Strut Tower bar.
There are 4 bolts (18mm)

Remove the engine cover, or your fuel rail covers.

Unplug the spark plug wires from the coils. Unclip and remove the coil packs off of the valve covers. Those bolts are 10mm and a deep socket helps a lot here since the bolts are sort of studded.

Throttle Body Removal:
Remove the 3 (10mm) Throttle Body bolts, the vent hose and the coolant lines.

Release the pressure on the tensioner pulley (15mm) by turning the pulley to the right (tightening) and pull the belt off from underneath the water pump and remove it. There’s another belt on the lower left balancer to AC unit. There’s another tensioner pulley on the lower left that will allow you to remove that belt as well.

Once you take that smaller belt off, remove that tensioner pulley bolt (15mm) because it gives you some more room later.
See less See more
Here’s a pic of the belt routing for reference:

You need to remove this pulley in order to get the water pump off. Here’s a pic of it with the bolt in it:

Water Pump Removal:
There are the two smaller hoses on the left side that the clamps/hoses need removed. The lower hose that holds the T-stat can be removed, or you can just pull the water pump out with it attached still (up to you). The upper hose port is seen in the pic which attaches to the upper radiator connection. I left that hose connected to the radiator.
Here are the 6 bolt (10mm) locations:

Optional: Remove the two bolts (10mm) that house the t-stat. When you put the new t-stat in, make sure you clock the gasket so that the one tiny nipple sits in the groove of the t-stat housing. Sorry I didn’t snap a pic, but you’ll see it when you are in there.

Power Steering Pump Removal:

3 (15mm) bolts hold the power steering pump bracket.

The hidden bolt on the bottom:

Now you can do one of two things. You can either remove the 3 bolts that hold the pump to the bracket:


You can pull the pulley off of the pump itself (this is the route I took)
You’ll need a power steering pulley puller.

Here’s how it looks installed onto the power steering pump:

Once you remove the bolts the bracket will come off. I sat a rag underneath the power steering pump to hold the weight and rested it on the block. This way you don’t have to disconnect any PS lines and risk getting fluid all over your alternator and killing it.
See less See more
  • Like
Reactions: 1
Balancer Removal:

First off, make sure the Transmission in in FOURTH GEAR. This is the 1:1 ratio gear in the V’s. Grab your big extension and remove the old balancer bolt. Some people have had trouble with flywheel slipping, but I didn’t have any trouble at all. I think the back wheels being on the ground obviously helped, and my stage 3 clutch grips like crazy. If for some reason you have trouble with slippage, you can jam an extension into the Flywheel teeth to hold the flywheel from turning.

Now in the GM tech .pdf directions for this part that I saw, it says to mark the balancer and crank. This is done to avoid extra vibrations from the balancer being clocked wrong. (just like your driveshaft causing vibes if it’s not indexed correctly)
So I took a punch, and made two tiny marks:

Now insert your new longer bolt. Here’s the one I got from Fastenal that worked like a charm:

Again, it’s a M16 -2.0 pitch x 120mm long bolt. It wasn’t fully threaded, but it still worked perfectly.

Thread it in pretty far, and grab your 3 ton 3 jaw puller. The jaws go on the INSIDE of the pulley. There are 3 sections cut out for the jaws to grab onto.

Crank away on the puller and you should start seeing the balancer come off. I was lucky to have a good 3 jaw puller from my buddy’s shop. I wouldn’t recommend borrowing one from AutoZone or Advance Auto. Rent one from Napa or somewhere reputable. There’s no reason to put yourself through hell using a piece of crap puller. Once the pulley is removed set it aside.

Timing Chain Cover Removal:

Now that the water pump is removed, and the power steering pump bracket is out of the way you’ll see the timing chain cover exposed. There are 8 bolts (10mm) along the sides and top. There are 2 (10mm) bolts that go into the oil pan. Remove all of these bolts and pull off the timing chain cover.

This will expose the cam gear and oil pump.
See less See more
Oil Pan Lowering:
Now it’s time to lower the oil pan. You aren’t going to remove the pan from the car, but you are going to lower it as low as possible. That means, you are going to remove all the bolts.
This has to be done in order to gain access to the oil pump pickup tube bolt/oring.

The dipstick tube is going to have to come out first. Remove the dipstick tube bolt (15mm) and pull up on the tube and it’ll pop out. Note the location of this. It’s in between the 2nd and 3rd exhaust runner on the passenger side. It has as slight angle to it so note that when removing so you know how to put it back in upon install.

There are lots of bolts around the pan and some of them are a tad difficult to get to. This is where bendy extensions, and some gear wrenches come into play. Sorry no pics. But if you are in it this far, you are no dummy and can figure it out  The ABS module lines are in the way of the front few bolts, so you’ll need to slightly bend around them in order to get to them.

Once all the bolts are out, the pan should fall down. If it doesn’t just hit on the side of the pan with your palm and it should pop down. Once it’s lowered, take a rag and clean off as much oil as you can off the surface. DO NOT remove the gasket material around the surface, just clean the oil off.

Cam Gear Removal:

Remove the 2 (10mm) bolts that hold the timing chain guide (black thing in pics) in place, and remove the guide.

Remove the 3 (10mm) bolts from the Cam Gear and remove the Cam Gear. The timing chain will still be attached to the oil pump, so you can let it hang down into the pan for now.

Oil Pump Pickup Tube Bolt Removal:
Now that the pan is loosened up, we can get after that oil pump pickup tube bolt (10mm)

This is where you need to have to focus, but have some patience. Stuff a rag into the oil pan opening so nothing falls in the oil pan, or you’ll be screwed. Once you have the rags in place, the oil pump pickup tube bolt can be reached with a 10mm Gear Wrench. I took the pic without a rag stuffed in yet, but you are going to stuff the rags in there!

*** When I loosened up the bolt with the gear wrench, I then took two fingers and slowly loosened up the bolt the rest of the way so that I had a good grip on it so it wouldn’t fall. Some have placed dental floss around the bolt so they could snag it if it fell (then snipped the floss off after) but if you placed the rags in the oil pan opening, you shouldn’t have much trouble. You will be just fine if you remain patient, and TAKE YOUR TIME***

Pull the tube down from the pump and separate it. You can see this magic oring that everyone is always talking about now.

Oil Pump Removal:

Now you can remove the 4 (10mm) bolts from oil pump and take it off the crank snout.
Here’s a pic with it removed.

You’ll see the Cam Retaining Plate there, now remove those 4 (10mm) bolts.

Here’s a pic of the Retainer Plate (left) Cam gear, Timing Chain Guide, and oil pump gear.

Once that is removed, the Cam is free to come out. Thread 3 of the bolts from the water pump into the end of the cam so you have something to pull on. OR, you can reach down into a lifter hole with a long screwdriver, and pop the cam forwards.

Be careful not to just yank it out. The cam has many lobes and this is one time in your life where you don’t want to be a caveman and just bang away lol. Finesse it out by slowly turning it back and forth and ease it out. Keep it perfectly straight while removing it or it’ll catch the lobes.

Here’s what you’ll be looking at after the cam is removed:
See less See more
Header / Exhaust Manifold Removal:

Get under the car and remove the bolts that hold your headers/manifolds to your exhaust system. I put jack stands under the collectors to hold them up while I remove the header bolts from up top to take the weight off and make the bolt removal much easier.

Remove the Spark plugs wires if you haven’t already. Get the spark plugs out of there as well since it’ll be easier to get the headers off and out of the way without them in. Besides, who wants to break a spark plug off in the head?

Remove the 6 (13mm) bolts (gear wrench is great here) on each header/exhaust manifold and the header will now be free. I didn’t completely remove the headers (but I had to remove them from the rest of the exhaust) and I let them rest on the jackstands, and moved them off to the side.

Intake Manifold Removal:

Relieve the pressure by pressing in the small valve core with a screwdriver on the front of the fuel rail (drivers side) Use a rag to catch the fuel that comes out.

Remove the curved hose that connects the TB to the Valley Cover.

Remove the fuel lines (you’ll need the 3/8” white plastic fuel line removal tool) and a rag to grab all the fuel that’ll come out:

Remove the Injector Clips:

Disconnect the front main fuel line to the intake:
You need to make sure the two tabs are pressed in evenly and then you’ll be able to disconnect the line.

You can leave the fuel rail and injectors on if you want, but I took them off. If you do take the rail off, there will be (surprise) more fuel that comes out.
Now it’s time to remove the manifold bolts. Here’s a good pic of all the bolts locations:
See less See more
Valve Covers / Rockers / Pedestal / Pushrods Removal:

Remove the 4 (8mm) bolts in the middle of the valve covers. The bolts and valve cover gaskets will come off with the covers.

Now you should see the all the rockers/springs/etc.

We need to get all of the rockers, and the rocker pedestal out of there. There are 8 (8mm) bolts holding all 8 of the rockers in on each side. Remove all of them as well as the rockers themselves. You will see the rocker pedestals laying there, so remove them as well.

Now your pushrods can be seen and removed. If you don’t for some reason use new pushrods, you’ll want to keep them in order. Here’s a pic of the pushrods, rockers, and pedestals removed and kept in order:

Now it’s time to remove all the Ground Bolts holding the main wiring harness (which is constantly in the way the entire install)
Here are the locations of the ground bolts that need to be removed:

Passenger side by the battery:

Passenger side rear:

Passenger side front:

Driver’s Side rear:

Don’t forget to remove this sensor (19mm deep well)

***There’s also an allen head plug that needs transferred over to the new heads that is right next to this sensor…don’t forget! No pic, but you’ll see it when you are in there***
See less See more
Head Removal:

Now time to remove the main head bolts:
The 5 upper bolts (10mm) are removed first

Now remove the 5 lower head bolts (15mm)

Then lastly, remove the 5 middle head bolts (15mm)

Now when you pull the heads off, coolant is going to come out. This is perfectly normal, just be aware. The main wire harness might get in your way, but if you’ve removed all the other connections, you should be able to pull the head right off. Once the heads are removed, you can pull the old head gaskets off as well. You can clean up the excess coolant up with a rag, or use compressed air with the rag over the top so it doesn’t spray all over the place.
Now clean up the head surface with some brakekleen and I used a plastic ice scraper since I read that online. Both together work very well. Cleanliness is KEY!! Make sure you clean off all the debris/gasket material. Then, clean it again. You can clean the carbon buildup off the tops of the pistons the same way (I did since I was there). If you do, clean the head surfaces again.

Transfer everything over from the old heads to the new heads:

Now line up your new heads next to the old heads. Drivers side next to drivers side, Passenger Side next to Passenger side. On the LS6, there are two “coolant plugs” on the top of the heads towards the back. They look just like the coolant bypass connections, and the block the coolant from coming out. Remove those from the old heads, and transfer to the new heads. Look around each side of the old heads, and transfer any bolts, connections, coolant sensor (put Teflon tape on it) or plugs to the new heads. Don’t forget that allen head plug on the front side of the drivers head either!

Lifter Tray / Lifters Removal:

Remove the lifter trays bolts (10mm, 1 per tray)

Some of the lifters will be attached to the trays and will pull out when you remove the trays themselves. Some of them will still be in the block, but most of them can be removed with your fingertips. If not, get a long extension magnet and pull them out.

You should now be finished with disassembly. Take a break, grab a few beers and marvel at how far you’ve stripped your car down. Maybe we should’ve just taken out the engine and stroked it, huh? Lol

Install new Cam:

Take the new boomstick out of the box, and brakleen all the debris off it first. I used engine assembly lube for the install that’s why it’s all red in the pic. The stuff is pretty nasty, but hey we aren’t afraid to get dirty right? You can use motor oil if you’d rather. The 3 water pump bolts threaded into the new cam help a lot more for installing it. That way you have something to grab onto when it gets close to all the way in. This is basically the same as removal. Just ease it in back and forth making sure not to just shove it in and clank the lobes against the block and bearings. Take your time.

When you get it in, install the cam retaining plate, put some Loctite on the bolts, and tighten the 4 (10mm) bolts to 18 ft lbs.

Install new Timing Chain / Crank Gear/ Cam Gear:

OK, now it’s time for the fun part….Lining up the dots on the crank gear and the Cam Gear.
Now depending on what timing chain setup you bought, your dots will look different.
Install the crank gear onto the crank snout. It’s keyed, so the dots won’t be lined up when you slide it on. Now install the old balancer bolt back into the crank. Now get your 15mm wrench, and turn it until it the dot points up at the 12 o’clock position.
Grab the timing chain, and drape it over the cam gear and under the teeth on the crank gear. Hold up tension on the chain and cam gear and line up the dowel pin on the cam with the extra smaller hole (not the 3 larger bolt holes) in the cam gear. Now turn the cam gear until the dot is directly facing down at the 6 o’clock position. While you turn the gear, the cam might move in and out a little bit while you are turning it to get the dot pointed downwards. If you are having trouble, you can thread one of the bolts into the cam to keep it lined up. Take your time and MAKE SURE the dots are lined up straight.

Once you’ve confirmed the dots are lined up, you can put some Loctite on the cam gear bolts (10mm) and tighten them down to 26 ft lb.
See less See more
Installing Oil Pump Oring / Oil Pump / Oil Pan Bolts:

It’s time to reinstall the new oil pump oring. Just put the NEW oring on the pickup tube and slide it down until it seats on the dimple of the tube itself.

Since you bought a new Melling Oil pump (highly recommended) it comes with two orings. There’s a green thicker oring, and a black thinner oring. Use the black one.

Now the Melling oil pump comes with two springs. The BLUE spring is for NORMAL pressure. The RED spring is for HIGH pressure. On mine, the red spring was installed. If the blue spring is in the box, you need to take your allen wrench (can’t remember what size sorry) and remove the cap screw on the bottom of the oil pump and replace the spring with the BLUE spring.

Now you can slide the oil pump onto the crank gear. You’ll have to turn the gear inside the oil pump to get it to line up with the crank gear. This is where you also need to insert the pickup tube back into the oil pump. Push the tube down a little bit, and get it centered with the hole in the oil pump that you are inserting it into. You won’t have to force it all, just make certain it’s lined up nice and won’t get pinched. If you pinch it, bye bye oil pressure. Once you get it in, put Loctite on the oil pump pickup tube bolt and re-install it to 9 ft lbs.

Now re-install all the oil pan bolts except for the front two that the timing chain cover sits on (10mm) to 106 inch lbs. Put a little dab of black RTV on the corners of the oil pan where the timing chain cover rests on it. This is a common spot that has the potential to leak.

Timing Chain Cover Install:

Before you reinstall the cover, we need to replace the front engine seal on the cover itself. Smack the seal out from the back of the cover with a hammer and screwdriver. Once you get it out, put the new one around the hole on the front of the cover and put a piece of wood over it and hit the piece of wood a few times instead of the seal itself. This will save the seal, and ensure that it seats evenly. Once the seal is seated, you need to put a bead of RTV sealant along the bottom of the timing chain cover. If there was any old RTV on it, make sure you clean up the sealing surface before you install it.

Now we can put the timing chain cover back on the front of the engine. Install the cover back on the front of the engine and install all 10 bolts (10mm). But DO NOT tighten them down all the way just yet.

Crank Pulley/Balancer Install:

Now it’s time to install the balancer. Put the balancer on the crank snout and thread the longer bolt that you bought, and tighten it up about a half an inch with the 15mm socket to ensure that the threads get started and the remove the longer bolt. Now put your OLD crank pulley bolt and tighten it until you can’t tighten it anymore. Now grab the torque wrench and torque the bolt down to 240 lb ft lbs. Now remove the OLD bolt.

Now install your NEW crank pulley bolt by hand until it bottoms out. Now tighten the bolt until 37 ft lbs. Now here’s where I took a sharpie and made a small line on the bolt. This is because the bolt needs stretched 140 degrees from where it is now. Grab your breaker bar, long pipe, and go medieval on the bolt until it goes 140 degrees from where the mark was made. Here’s a pic……

Now that you have the balancer installed, the timing cover will be aligned and the timing chain cover bolts (10mm) can be tightened to 18 ft lbs. Don’t forget the two oil pan bolts (10mm) up front that go through the oil pan into the timing chain cover and tighten them down to 106 inch lbs.
See less See more
Lifter Trays / Lifter Install:

First thing’s first. Soak your lifters in oil until the bubbles stop popping up.

Now put the lifters into the end of the trays. They can only go in one way, so put four lifters in each tray and install them into the block. They should slide right in.

Now install the other trays. (4 lifters per tray, 4 trays total = 16 lifters) Now put Loctite on the threads of the lifter tray screws (10mm) and install them. Tighten them to 106 inch lbs. Do NOT over tighten these bolts, as you have a chance to strip them out if you do.

Cleaning the Bolt Holes

Now while the bolt holes are nice and open right there, it’s time to clean them up so that your new bolts (or studs) can be installed nice and cleanly. Some people run a tap through the hole to clean them up. I’ve even seen people cut a slit in the old bolts and use it as sort of a tap. What I did was use brakekleen and compressed air. I filled each hole entirely with brakekleen until it ran out the holes. Doing this you can see some of the grit/grime/dirt come out with the brakeleen. I let it sit inside the hole a bit, and then taking a rag over the top (so it doesn’t get all over the place) take your compressed air and spray air in the hole. You may have to do it a few times a hole, but it’s worth it so the new bolts (or studs) can be installed cleanly.

Installing Heads:

Installing ARP Head Studs

If you are using the ARP head studs, then put a dab (don’t need much) of the lube that came with the studs on each of the threads. Also, put some on the bottom of each stud as well. The smaller 5/16 diameter (1/8” allen wrench) studs go in the upper 5 holes in the block. (15-13-11-12-14 the torque sequence pic below. The larger 7/16 diameter (3/16” allen wrench) studs go in the lower 10 holes (1 thru 10) in the same torque sequence pic below.

Install each stud until they BOTTOM OUT HAND TIGHT only. If any of them don’t go in easily, the threads are still dirty and have gunk in them. Remove the stud and try some more brakekleen and compressed air.

Once you have all the studs in, put the head gaskets on.

I’ll say it again, because it’s important. Cleanliness is key. Again, make certain that the surface of the heads are pristine clean. You don’t want to do this job twice because you didn’t clean the surface well enough. If there’s anything on the block surface, use some brakekleen and either rub off the debris, or scrape it off with your plastic ice scraper.

Now lay the new head gaskets on the block orientated correctly and one the correct side. They are not the same, and go a certain way. Make sure the word “FRONT” is towards the front bumper of the car. Depending on the brand of gasket you chose, it might also say “TOP” or “BOTTOM”. You can double check and make sure no water jackets or holes are covered.

Now slide the head down over the studs and on top of the head gasket.

Install the 12 point nuts on all of the studs hand tight.

The smaller 5/16 diameter studs (the 12 point nuts are 3/8”) are torqued in three equal steps
To 25 ft lbs. I did 8 ft lbs, 16 ft lbs, then 25 ft lbs.

The larger 7/16 diameter studs (the 12 point nuts are 1/2”) are torqued in three equal steps
To 80 ft lbs. I did 26 ft lbs, 54 ft lbs, then 80 ft lbs.
See less See more
Installing OEM Head Bolts:

I’ll say it one more time, because it’s that important. Cleanliness is key. Again, make certain that the surface of the heads are pristine clean. You don’t want to do this job twice because you didn’t clean the surface well enough. If there’s anything on the block surface, use some brake kleen and either rub off the debris, or scrape it off with your plastic ice scraper.

Now lay the new head gaskets on the block orientated correctly and one the correct side. They are not the same, and go a certain way. Make sure the word “FRONT” is towards the front bumper of the car. Depending on the brand of gasket you chose, it might also say “TOP” or “BOTTOM”. You can double check and make sure no water jackets or holes are covered.

Now slide the heads onto the block surface. The short stubs on the block will hold the heads in place.

Install all bolts hand tight.

The smaller (10mm) bolts go in the top 5 holes (15-13-11-12-14 location in the torque sequence pic below)

The larger (15mm) bolts go in the lower 10 holes (1 thru 10 location in the sequence pic below)

The Torque Value and sequence for the OEM head bolts are as follows:
Step 1 (Bolts 1-10) to 22 ft lbs.

It helps to do the next part by drawing a horizontal line on the head of each 15mm bolt in order to better keep track of how far you’ve torqued each bolt.

Step 2 (Bolts 1-10) 90 degrees
Step 3 (Bolts 9-10) 90 degrees
Step 4 (9-10) 50 degrees
Step 5 (11-15) 22 ft lbs

Here’s the torque sequence pic:

Once you are done, you should be looking at something like this:

****Once you have everything buttoned down. Take your 24mm socket and breaker bar, and turn the engine over manually. Now listen for any clanking or abnormal noises. If you hear anything out of the ordinary stop now, and figure out what went wrong.****

Figuring out Pushrod Length:

Now if you don’t already know what size pushrods you need, this is where you need to figure it out.

Instead of trying to reinvent the wheel, here’s a good article on Figuring out Pushrod Length

Figuring out Preload:

You’ll need to bust out your dial gauge and determine Preload.

Here’s a good writeup on this:

Determining Wipe Pattern:

This is a great write up on this. I used a sharpie and colored the valve stems completely.

**I had to use the shims that came with the Yella Terra rockers in order to get the rockers exactly in the center of the valve stems.**

FYI: After I measured, I ended up using 7.395 push rods. Stock are 7.400

Installing Push Rods / Pedestal / Rockers:

If you are installing stock rockers:
Now that you’ve figured out the pushrod length, slide all 16 pushrods into the holes that lead to the tops of the lifters.
Place the Rocker pedestal back onto the heads. Put Loctite on the threads of the rocker bolts (8mm). Also, put RTV on the tips of the bolts since you don’t want coolant/water creeping through there. Tighten them down to 22 ft lbs.

Once they are all installed and torqued, turn the engine over manually by putting your 24mm socket on your breaker bar back over the balancer bolt and turn to the right. Listen for any abnormal sounds and make sure nothing is in a bind.

If you are installing Yella Terra rockers:

Here are the instructions that come with the rockers:
See less See more
Valve cover / Gasket install:

When I tried to use the Yella Terra rockers with the stock valve cover gaskets, the rockers hit the valve covers. They are too tall, so I installed the taller Yella Terra gaskets and I also dremmel’ed some more material off the inside of the valve covers in order to get them to stop hitting.

If you use the stock rockers: then you can use stock valve cover gaskets. You’ll have to freeze them for a bit to shrink them enough to install them onto the valve covers.

If you use Yella Terra rockers: then you’ll have to use the taller YT5132 valve cover gaskets. You’ll need to soak them in hot water for a bit to make them more pliable.
Also there are nuts that need to be installed onto the bottoms of the valve cover bolts.

Now you can reinstall the valve covers onto the heads. The valve cover bolts (8mm) need to be tightened hand tight.

Water Pump Install:

Put some blue Loctite on the water pump bolt threads and then reinstall your 6 (10mm) bolts hand tight through the holes in water pump and put the two new gaskets against the water pump. Make sure they line up correctly and don’t cover the water jackets. Now do the first pass at 11 ft. lbs, and do another pass at 22 ft. lbs.

Once you’ve installed the water pump and tightened the bolts, you can put the little pulley back on the lower right of that water pump picture (above). I don’t have a torque spec, but just tighten it down a little past hand tight.

Also, reinstall the smaller pulley that holds the AC belt to the balancer if you haven’t already. Tighten the pulley bolt (15mm) to 22 ft lbs.

Don’t forget to reconnect the two coolant lines on the passenger side that you removed earlier.

Power Steering Pump Install:

Just reverse the process of the removal. Put some blue Loctite on the threads and replace the 3 (15mm) bolts on the bracket and tighten them to 22 ft lbs. Replace the pulley (if that’s the route you took) see pic from the install above.

Now you should have all pulleys installed and you can install the smaller belt around the A/C pulley to the balancer. You can also install the longer belt as well. Here again is the belt routing:

****Again, just to be entirely sure…..Take your 24mm socket and breaker bar, and turn the engine over manually. Now listen for any clanking or abnormal noises. If you hear anything out of the ordinary stop now, and figure out what went wrong.****
See less See more
Injectors/Fuel Rail:

Depending on which injectors you went with, now you can install them into the intake and fuel rail. Make sure you put a dab of oil on all the orings upon reinstalling them. If you see any of the orings damaged, replace them.

I went with a LS2 fuel rail to clear the top of Fast Intake. The rail is tall enough to clear the intake runners, but then it’s too tall to hit the bolt holes that are in the intake. Here’s a picture of what I mean:

You’ll need to either machine some spacers, or use washers stacked on top of each other to make up the difference.

Before installing the intake manifold, tighten down all the wiring harness ground bolts to the heads and block. If there is any debris on the connectors, clean them off to ensure a good ground. All the locations are posted in pics in the removal phase.

Fast 102 Intake Manifold Install:

I don’t need to re write all of the Fast 102 instructions.

That said, here’s a few notes that pertain to the install: (Before you do this, change out the valley cover bolts with the bolts provided with the Fast Intake)

It says to reinstall the coolant crossover line before you put the intake on. I put the intake on first, then put the coolant crossover line on since it had to be re-bent to clear the slightly bigger Fast intake.
Here’s a pic of the coolant crossover line:

Put that off to the side for now, as we will install it after the intake is on and torqued down.

Make sure your connections are as follows (looking at back of Fast 102):
The brake booster hose will stretch far enough to reach the actual brake booster but you’ll need to clamp (I used hose clamp) the hose to the brake booster connection. If you don’t, it will pop off.

As far as the plug, I used the stock plug and dabbed a little RTV in there to make sure it sealed up well. If yours is damaged, replace it.

Lastly, install the MAF (ours is grommet style so drill out intake with 3/8” drill bit and make certain you get all the shavings blown out) in there and tighten down the hold down screw to 19 INCH lbs.

When you have it installed, place the intake on the block (don’t slide it) and connect the MAF and the brake booster hose to the back of the intake. Then pick it up and place it the rest of the way onto the valley cover and insert the 10 long intake bolts.

Here’s the torque sequence for the Intake:

Use TWO passes when tightening them down. The first pass is 45 INCH lbs, and the second pass is 89 INCH lbs.

Go through the rest of the instructions, and get everything else buttoned up.

Once you get the intake bolted down, the fuel lines hooked back up to the fuel rail, and the injectors clips connected you will be looking at this:

You notice the LS6 fuel line has two brackets on it that won’t match up to anything. I ended up taking a cut off wheel, and slicing them off. I doesn’t look that bad, but I will most likely replace it with AN line in the future. Here’s a pic of it before I cut the brackets off:

Now you can install the coolant crossover line. Just bend it a little, and then keep tweaking it until it fits into the two spots/holes on each head flush/straight up. The bolts are only torqued to 106 INCH lbs. Here’s a pic of it in process of being bent and re-bent. (Disregard using the old curved vacuum hose in the pic I was still trying to make it work but it won’t. Most of the time it just breaks apart upon removal anyways)

P.S. If you bought an oil catch can, now’s the time to install it.

You can put the TB on with the intake, but if you leave it off for now, it will give you more room to work the radiator and fans down into the engine bay later.

Man, I’m sick of typing….but at least we are almost done!
See less See more
Header Install:

Now it’s time to put the headers back on. Now since your headers are sitting on jackstands, just grab them and put one header bolt through a hole and through your gasket (make sure you put them on facing correctly as they are marked) and thread the bolt into the block. Repeat this process for all
(13mm) bolts (gear wrench is great here) until all the bolts are in at least half way.

Now reconnect the bolts to the rest of the exhaust underneath (you didn’t crank all the header bolts down so you could leave yourself some play) and then you can go back up top and tighten the header bolts hand tight.

Once the header bolts are all in hand tight, go back down and tighten the headers to the rest of the exhaust, and now you can tighten the header bolts down to 18 ft lbs.

Now you can reinstall the dip stick to the oil pan. Replace the dipstick tube bolt (15mm) and push down on the tube and it’ll pop back in. Remember: It’s in between the 2nd and 3rd exhaust runner on the passenger side. It has as slight angle to it so if you can’t get it, have someone help you guide it in from the top while you guide it back into the oil pan hole.

Radiator, Fans and A/C condenser Install:

Now you can slide the radiator and fans (as one) back down into the engine compartment. If you removed the A/C condenser, you can put that in after the radiator and fans are back in. Make sure when you do this, you are careful not to bend any of the fins on the radiator. There are two holes with rubber rings in the frame awaiting the two posts in the radiator. Line these up and it will sit nice and snug.

Reconnect the larger lower radiator hose (drivers side), the upper smaller hose (drivers side).
Reinstall the Phillips screw that holds the A/C condensor line to the fan shroud, and plug in the gray connector that plugs into the front of the fans.

Reconnect the upper larger hose to the water pump.
I lost a few pics of the radiator process, but just found this writeup by googling cts-v radiator install, which include some good pics:

Now you can use the hose from the radiator and connect it to the coolant crossover line:

Now reconnect the A/C condenser to the the front of the radiator. There are a few Phillips screws headed bolts (but use a 10mm socket) for these.

If you removed the A/C condenser, then replace the orings (part # 25740416) now, and only retighten the screws to 14 INCH lbs. If you over tighten them they will strip out.

Now reconnect the 2 black main hold down brackets at the front of the car with the 2 (10mm) screws. Tighten them a little past hand tight.

Throttle Body Install:

You could’ve put the TB on with the intake, but if you left it off until now, it will give you more room.

Once you’ve got it all on there (including the TB gasket into the Fast 102 intake, install the throttle body onto the intake with your four screws. Since the Fast 102 uses a LS2 style throttle body, make sure to clock the TB Motor to the left (passenger side) and tighten down the screws between 70-89 INCH lbs. I used 79 in/lbs.

Now you’ll have to install your LS6 to LS2 TB harness. It’s pretty self-explanatory here. You’ll see which connectors fit into where once you are at this point.
See less See more
Spark Plugs / Wires / Coil Packs:

Install your new spark plugs (which you dabbed some anti-seize on) and install them in hand tight, and then a quarter turn.

I installed my plug wires onto the plugs and let them hang for now until I put the coil back on.

Now reinstall the coil packs, tighten down the (10mm – long socket) bolts and insert the spark plug wires into the coil themselves. Don’t forget to reconnect the main harness connections to the coil pack connections.

Home Stretch:

Replace your oil filter with a new one. Install 6 and (roughly a half) quarts of oil. Refill your radiator through the coolant overflow reservoir (located in back on the drivers side) with 50% Water and 50% Dexcool. I think I remember going through a little bit more than a gallon of Dexcool. Leave the cap off because once you start the car and let it idle, it will take more coolant/water.

Look around in the engine bay for any connections, grounds, extra tools, body parts, and make sure everything looks good. Now it’s time for the moment of truth!!!

Pull two fuses in the front (passenger side) fuse box. The two fuses are under the hood fuse box. There is one called ODD/INJ/COIL and one called EVEN/INJ/COIL which disable both the ignition coils and fuel injectors for each bank.

This will allow the engine to turn over with the turn of the key, but not actually start up. Crank over the key for 5 seconds and listen for any crazy noises. If nothing, you are ready to have your tuner tune you up. Or, if you are feeling good, put the fuses back in and crank it up.

Once started / Things to watch:

If it won’t idle, hold the gas down a little bit and keep it idling. Hopefully it will learn itself out.

The engine will be noisy for about 8 seconds. The lifters haven’t filled up with oil yet.

Watch the oil pressure intently!! It should come up to 30-50psi after a few seconds. If it doesn’t, shut the car off. Something isn’t right.

The engine bay is going to smoke. Coolant, oil, grease, etc is going to be burnt off.

Once you can get it idling, add water/coolant as needed. Once it’s up to operating temp, and the coolant/water is filled up, put the cap on the coolant reservoir.

Watch for leaks underneath!

If no problems, then you can drive it if you decide to. Just keep the rpm’s down under 4k for the first day. The springs need to heat cycle overnight, so it’s ok to redline the car the next day. From now on no more beating on your car until it’s reached operating temperature. Unless of course you like snapping valve springs.

If you are a little more cautious like me, call the tuner to come over and hook you up without driving it. I’m probably being too careful, but I didn’t want to wash out the rings or foul out the plugs since I added bigger injectors. Up to you.

I think that’s about it. If I missed anything, sorry let me know. I’m going to make these instructions into a .pdf, I’ll just have to add pics instead of the links. I’d like to thank jmX at, Darkman on caddy forums, caddy forums, and ls1tech. I’ve learned plenty of things along the way from each. Also thanks to my buddy Lance for helping me figure out the pushrod length and the wipe pattern. He's old school.....and badass!
See less See more
  • Like
Reactions: 1
The two fuses I mention are under the hood fuse box. There is one called ODD/INJ/COIL and one called EVEN/INJ/COIL which disable both the ignition coils and fuel injectors for each bank.

Thanks Darkman!

nevermind....I was able to edit the thread. Whew lol
Nice writeup!

You make the entire process look pretty easy..

Question for ya - how long did it take start to finish?
It's really not that difficult if you are handy with a wrench, pay attention to detail, and are patient. I went at a leisurely pace, made sure I kept bolts with the pieces that I took off, and had everything laid out and kept separate. Made it A LOT easier when it came to reassemble. I also double checked everything, and sometimes triple checked torque values, and kept everything clean clean clean. <- The key to building any engine.

As far as how long did it take....that's a difficult question to answer, because I had to go here and there for misc parts, or wait for something to be shipped. Then it takes a few days for pushrods after you figure out which length you need. I did everything over the span of about 2 weeks. I would say you could get this done in a full weekend (as in start in the morning and work til night - stopping for lunch) IF you had all the parts lined up and ready to go. But then you would have to have a couple of sets of different length pushrods at your disposal because you wouldn't know the length without checking first.

Thanks everyone. Especially Darkman....he is the most helpful guy on the planet. :worship:

Here's a link to the conversations and some learning I did before the build. Thanks to everyone that helped me along the way!!
See less See more
What spark plugs are most of you running?
Wow, Great write-up!! However I don't like to read Too much so why don't you just come on over and do my conversion!! LOL
Lolz, my hourly rate isn't that high, but I take my time so that's what'll getcha
1 - 20 of 37 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.