** The best LS6 swap writeup ever! **
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TECH Junkie
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** The best LS6 swap writeup ever! ** Yep here's another fantastic writeup from yours truly. Enjoy it!
LS6 Intake Swap Walkthrough
Needed:
LS6 Intake Manifold (of course!)
Oil Pressure Sending Unit Socket
3” extension
10mm long socket
8mm short or long socket
Pliers
Optional:
LS6 Style coolant crossover tubes
Dremel or other grinding tool
Suggested:
New knock sensors and harness (Especially 98’s)
New oil pressure sending unit
PCV delete or catch can install
Ok I am going to start off by saying I followed the LS1Howto.com guide to an LS6 intake install and knowing what I know now, I would do it VERY differently. I ended up breaking the oil pressure sending unit as most people do and it took me literally an entire day (like 8 hours) to locate and get a replacement. I believe doing it this way will prevent you from breaking the oil pressure sending unit.
On a side note: I believe that whether you break it or not doing it LS1Howtos way depends entirely on the car on my car the brake booster hose was tucked under a wiring harness which leads it straight into the sending unit, if it is above the wiring harness I think you can probably yank it out without breaking it everytime as long as the other end is disconnected. Just my .02
Coolant Lines
You should decide whether or not you wish to use the LS6 style coolant crossover lines that connect the heads to each other. The absolute best solution would be to use basically a front and a back coolant line and connect them down the middle in an I shape. But I opted to use the existing LS1 style coolant tubes because they will cool the problem cylinder #7 better. It was exactly this reason that I chose NOT to use the LS6 style coolant crossover lines. However, if you just want to get it done quickly and easily I suggest buying coolant crossover tubes from thunderracing or some other sponsor.
Knock Sensors
This is especially important for 98 model cars , you should replace the knock sensors and harness, 1998’s had overly sensitive knock sensors that caused them to detect a constant 3-4* of false knock. The part number for the knock sensors is 10456603 which you need two of, and the harness (for 98’s anyway, it MAY be different for other years I am not sure at all) is part # 12601822 which you only need one of. Even if you’re car is a 99+ I suggest replacing them while you’re there since mine were very rusted.
!PCV / Catch Can
This is of course a very debated subject but in my opinion the PCV system on the LS1 is so poorly designed it is worthless, so I opted to cap off all PCV ports and buy the Metco oil cap breather from Speed Inc.worth every penny. If breathers aren’t you’re bag then I would suggest a catch can. The whole idea is to keep oil out of your new intake manifold!
Now that you are educated on the matter, lets get down to business!
1. Start by taking the air lid, MAF and bellows assembly apart, if you need me to explain this to you , you may want to reconsider doing this swap yourself.
2. Now you want to remove the coolant tubes going through you’re throttle body if you still have them (this may be a good time to do the coolant bypass mod!) careful a little coolant will come out.
3. Disconnect the throttle cable and tuck it behind a hood strut so its out of your way for good.
4. disconnect all the sensors on the throttle body and remove it from the car, put it somewhere safe
5. remove all tubes connected to the intake manifold or throttle body, the evap tube (I believe that’s what its called?) on the drivers side has a small white/gray clip that needs to be pushed in to release it. The rest just pull off. You’re best bet here is to remove all of the PCV tubing (carefully) even if you’re not deleting PCV just to get it out of the way. There is also a small vacuum line on the back of the intake on the passengers side that needs to be removed and unplug the MAP sensor and oil pressure sending unit connector (CAREFULLY!)
6. now you want to disconnect all 8 fuel injectors by pushing the metal clip up and pulling the body out. Unplug the evap valve connector, and the big connector for the coil pack harness. Basically anything that looks like its going to be in the way EXCEPT the fuel line going to the fuel rails, DON’T mess with that!
7. now unbolt the 4 10mm bolts holding the fuel rails on and YANK them off, they will just kind of pop off the manifold but be careful. Once they pop off carefully pivot the fuel rails out of the way somewhere in the engine bay.
8. Now its just you and the intake manifold! Remove the vacuum hose connect to the brake booster. Now here is THE MOST IMPORTANT STEP squeeze you’re (hopefully) little hands behind the intake manifold and slide the oil pressure sending unit socket over the unit and get a wrench on it. Once its broken loose you can probably get it the rest of the way out with you’re hand. Now that you have the sensor out the rest is easy as pie!
9. take the 10 8mm bolts out of the intake manifold the front 6 will come all the way out, the back 4 will not. Yes, you automatic guys, the very last bolt on the passengers side is DIRECTLY below the filler tube for the trans (thanks GM!) I had to bend mine about 1 ½” to the drivers side to get the bolt out.
10. Now yank the intake out, you may have to play with the remaining 4 bolts a bit to get the manifold unseated.
11. Now you have the manifold out if you are replacing the knock sensors go ahead and do that now, I don’t recall what size socket they were but I want to say it is 7/16. In my case I also took the opportunity to vacuum some of the crap out of the space between the heads and the valley cover on either side.
12. Now if you are using the original coolant tubes go ahead and grind some of the ribs off the bottom of you’re LS6 intake, it will take quite a bit of guess work, but I spread some brake grease on the coolant lines, fitted the intake, and ground where there was grease on the manifold, worked pretty well! Just don’t forget to wipe it off real good.
13. Don’t forget to transfer you’re map sensor from the ls1 intake to the ls6
14. Now carefully put the ls6 in and don’t forget to put the 4 back bolts in before it goes in! tighten it down and make sure it looks tight, these bolts only need 37 ft/lbs so don’t go crazy. – make sure you don’t have any hoses or harnesses under the manifold when you bolt it down, I had to take mine back off because I tightened it down with the oil pressure sending unit connector in the #7 intake port
15. put that oil pressure sending unit sensor back on carefully and plug it back in along with everything else back there.
16. snap the fuel rails back in and pretty much just put everything back together in reverse of installing it.
17. If you are deleting PCV don’t put the hoses back on, run one 3/8” from valve cover to valve cover and block the rest off with 3/8” nipples and of course you need a breather.
This took me a total of about 11 hours over the course of 3 days, but I was going seriously slow, working alone, and had to go on a road trip to practically f*cking Wisconsin to get a new oil pressure sending unit.
Have fun!
LS6 Intake Swap Walkthrough
Needed:
LS6 Intake Manifold (of course!)
Oil Pressure Sending Unit Socket
3” extension
10mm long socket
8mm short or long socket
Pliers
Optional:
LS6 Style coolant crossover tubes
Dremel or other grinding tool
Suggested:
New knock sensors and harness (Especially 98’s)
New oil pressure sending unit
PCV delete or catch can install
Ok I am going to start off by saying I followed the LS1Howto.com guide to an LS6 intake install and knowing what I know now, I would do it VERY differently. I ended up breaking the oil pressure sending unit as most people do and it took me literally an entire day (like 8 hours) to locate and get a replacement. I believe doing it this way will prevent you from breaking the oil pressure sending unit.
On a side note: I believe that whether you break it or not doing it LS1Howtos way depends entirely on the car on my car the brake booster hose was tucked under a wiring harness which leads it straight into the sending unit, if it is above the wiring harness I think you can probably yank it out without breaking it everytime as long as the other end is disconnected. Just my .02
Coolant Lines
You should decide whether or not you wish to use the LS6 style coolant crossover lines that connect the heads to each other. The absolute best solution would be to use basically a front and a back coolant line and connect them down the middle in an I shape. But I opted to use the existing LS1 style coolant tubes because they will cool the problem cylinder #7 better. It was exactly this reason that I chose NOT to use the LS6 style coolant crossover lines. However, if you just want to get it done quickly and easily I suggest buying coolant crossover tubes from thunderracing or some other sponsor.
Knock Sensors
This is especially important for 98 model cars , you should replace the knock sensors and harness, 1998’s had overly sensitive knock sensors that caused them to detect a constant 3-4* of false knock. The part number for the knock sensors is 10456603 which you need two of, and the harness (for 98’s anyway, it MAY be different for other years I am not sure at all) is part # 12601822 which you only need one of. Even if you’re car is a 99+ I suggest replacing them while you’re there since mine were very rusted.
!PCV / Catch Can
This is of course a very debated subject but in my opinion the PCV system on the LS1 is so poorly designed it is worthless, so I opted to cap off all PCV ports and buy the Metco oil cap breather from Speed Inc.worth every penny. If breathers aren’t you’re bag then I would suggest a catch can. The whole idea is to keep oil out of your new intake manifold!
Now that you are educated on the matter, lets get down to business!
1. Start by taking the air lid, MAF and bellows assembly apart, if you need me to explain this to you , you may want to reconsider doing this swap yourself.
2. Now you want to remove the coolant tubes going through you’re throttle body if you still have them (this may be a good time to do the coolant bypass mod!) careful a little coolant will come out.
3. Disconnect the throttle cable and tuck it behind a hood strut so its out of your way for good.
4. disconnect all the sensors on the throttle body and remove it from the car, put it somewhere safe
5. remove all tubes connected to the intake manifold or throttle body, the evap tube (I believe that’s what its called?) on the drivers side has a small white/gray clip that needs to be pushed in to release it. The rest just pull off. You’re best bet here is to remove all of the PCV tubing (carefully) even if you’re not deleting PCV just to get it out of the way. There is also a small vacuum line on the back of the intake on the passengers side that needs to be removed and unplug the MAP sensor and oil pressure sending unit connector (CAREFULLY!)
6. now you want to disconnect all 8 fuel injectors by pushing the metal clip up and pulling the body out. Unplug the evap valve connector, and the big connector for the coil pack harness. Basically anything that looks like its going to be in the way EXCEPT the fuel line going to the fuel rails, DON’T mess with that!
7. now unbolt the 4 10mm bolts holding the fuel rails on and YANK them off, they will just kind of pop off the manifold but be careful. Once they pop off carefully pivot the fuel rails out of the way somewhere in the engine bay.
8. Now its just you and the intake manifold! Remove the vacuum hose connect to the brake booster. Now here is THE MOST IMPORTANT STEP squeeze you’re (hopefully) little hands behind the intake manifold and slide the oil pressure sending unit socket over the unit and get a wrench on it. Once its broken loose you can probably get it the rest of the way out with you’re hand. Now that you have the sensor out the rest is easy as pie!
9. take the 10 8mm bolts out of the intake manifold the front 6 will come all the way out, the back 4 will not. Yes, you automatic guys, the very last bolt on the passengers side is DIRECTLY below the filler tube for the trans (thanks GM!) I had to bend mine about 1 ½” to the drivers side to get the bolt out.
10. Now yank the intake out, you may have to play with the remaining 4 bolts a bit to get the manifold unseated.
11. Now you have the manifold out if you are replacing the knock sensors go ahead and do that now, I don’t recall what size socket they were but I want to say it is 7/16. In my case I also took the opportunity to vacuum some of the crap out of the space between the heads and the valley cover on either side.
12. Now if you are using the original coolant tubes go ahead and grind some of the ribs off the bottom of you’re LS6 intake, it will take quite a bit of guess work, but I spread some brake grease on the coolant lines, fitted the intake, and ground where there was grease on the manifold, worked pretty well! Just don’t forget to wipe it off real good.
13. Don’t forget to transfer you’re map sensor from the ls1 intake to the ls6
14. Now carefully put the ls6 in and don’t forget to put the 4 back bolts in before it goes in! tighten it down and make sure it looks tight, these bolts only need 37 ft/lbs so don’t go crazy. – make sure you don’t have any hoses or harnesses under the manifold when you bolt it down, I had to take mine back off because I tightened it down with the oil pressure sending unit connector in the #7 intake port
15. put that oil pressure sending unit sensor back on carefully and plug it back in along with everything else back there.
16. snap the fuel rails back in and pretty much just put everything back together in reverse of installing it.
17. If you are deleting PCV don’t put the hoses back on, run one 3/8” from valve cover to valve cover and block the rest off with 3/8” nipples and of course you need a breather.
This took me a total of about 11 hours over the course of 3 days, but I was going seriously slow, working alone, and had to go on a road trip to practically f*cking Wisconsin to get a new oil pressure sending unit.
Have fun!
