LGM Long Tube Headers
All of these installations are to be performed at your own risk!!!!
Step 3 (Installation of LGM Long Tube Headers):
The first thing you want to do is jack the front of the car up somewhere around 20".
Once the car is secure on stands you can begin installing the headers. Installing the headers into the car really is not that bad if you take your time and look for obstacles. Start with the drivers side from the bottom. Before you do so, make sure you remove the 15mm bolt that holds the ground strap to the block. There is also another wire grounded their so don't forget about it when you replace it.
Now we are ready to install the driver's side header from the bottom. The pic below shows the difference between the OEM manifolds and the LGM header. Slide the driver's side header up from the bottom. It may take a few tries to get it through and around the bellhousing but it should go through after some time. You do not have to force it, it will fit. Some people may even jack there engine up a little but I did not have to do this. There is a metal line that is for the clutch that may get in your way a little. Just pull this out of the way. You can see this line in the above pic on the right hand side next to the front O2 sensor plug. It has a little slack to it.
Once the driver's side header is up into the engine bay you may start threading the bolts in. Put one bolt in the middle first without the gasket to hold the header up. A second pair of hands would be good here but it is not necessary. I was able to do it fine by myself. You should of purchased a set of F-body gaskets. These are the ones with the round holes instead of the oval shaped holes that the car calls for (see pic).
Once the header is in place you can place the gasket in and thread one of the end bolts in. Tighten it down several turns and remove the middle one. Set the gasket and thread the rest of the bolts in several turns. DO NOT TIGHTEN THESE BOLTS YET.
Now we are ready for the passenger side. To do this we must first take off the passenger side valve cover. Remove the four 8mm bolts running down the center of the valve cover. You do not need to pull these bolts out of the valve cover, just undo them and pull up on the cover.
Now disconnect the two hoses that go to the top of the valve cover and remove the valve cover.
After you remove the valve cover you can slide the passenger side header in from the top. Do this slowly and watch for obstacles. It is a very tight fit around the starter area but I was able to install without removing the starter. Keep checking for any obstacles from above and below if you encounter resistance. Once you get the header in place you can use the same process to install as you did with the driver's side remembering to only thread the bolts in several turns for now. You can now thread your oxygen sensors in at the bottom. I bought this set used and had to cut the OEM front oxygen sensor plugs off of my stock manifolds and splice that plug on to the OEM rear oxygen sensor lines. I would like new but I am impatient and getting a solid answer out of any vendor when things are back ordered is a near impossibility. It was the same case with my Borla Quad Stingers. Anyway, if you run into this situation, the plug on the OEM rear sensors has the wires labeled A, B, C, and D.
The Tan wire is A, the purple wire is B, and C&D are both brown. Just take one at a time and splice the front O2 sensor plug in place of the rear OEM O2 sensor plugs. Common sense tells us that C would be the first brown wire so that is why I suggest to cut one wire than splice one wire so you don't mix up the browns. If it event matters, not sure. I think a new set of LGs come with adapters but I was unaware of this and ended up cutting the lines after someone at LGM told me on the phone I needed to do that. They said nothing about the adapters. Anyway, it works because I have had my dyno tune and the tuner could read the front oxygen sensors which is needed to adjust the air/fuel ratio.
With both headers in place you can now loosely attach them to the bellhousing braket.
