I am always seeing on the forums or on the facebook groups, people asking questions about how the cam caps are to be installed. Torque specs, cam cap direction, mis-matching caps, etc. So while I replaced my head, I figured I would take some pictures and clear the air on this topic.
First off, you CAN NOT swap cam caps from one head to the other. You HAVE to use the cam caps that originally came with the head. The caps are machined to fit that particular head, much like rod caps and rods. If you do, the cams will most likely bind up and you won’t be able to turn the cams by hand. You can imagine what would happen if you tried starting the car like this; no good.
During installation of the cams, you should remove the rocker arms first. Then, install the cam caps and bolt them down to 14-15ft.lbs in a 2 or 3 step sequence. You should start by bolting the cam caps in the center first, working your way out to each side. Once they are installed properly, rotate each cam. With the rocker arms removed, they should spin pretty easily. Once you are satisfied, remove the caps and cams and put your rocker arms back in. Use the same method for re-installing the cams with rocker arms in place.
Now, I will touch in the cam cap direction/placement which is one of the more popular questions. Each individual cam cap have arrows and markings to tell you what cam cap they are.
The cam cap furthest to the right in this picture says “I3”. This means it goes on the intake cam, 3 caps in from the cam gear. From right to left, the cam cap orientation will be I1, I2, I3, I4, I5. The last cap will not say I6, however.
The picture here shows the last cam cap on the intake cam. As you can see, it doesn’t say I6 anywhere on it. Note the large arrow and the direction it is pointing in. Also note that this is the cam cap that the 1G CAS (Cam Angle Sensor) bolts to. The side of this cam cap will look different than the cap in the same position on the exhaust cam.
This is the, would be E6 cap. You can easily see the difference in shape/width between it and the “I6” cam cap. On the “E6” cap, there is no provision for the 1G CAS. Also note the arrow and the direction it is pointing in.
The next two pictures are the I3 and I4. There are a few things to note on each individual cam cap that is a “middle” cap. The arrows. On the I3 cap, the arrow is pointing up as should the rest of the intake caps.
This is the E3 cap. Again, notice the arrow. The exhaust caps arrows point down where as they point up on the intake cam.
This is the I1 cap. The arrow is pointing up. The I1 and E1 cam caps are much wider than the rest.
This is the E1 cap. Note the arrow. It is also pointing up, unlike the rest of the exhaust cam caps, but it is clearly stamped as the “E1” cap.
Above is a picture of the entire head in which you can see all of the cap caps and their markings all in one picture. It is critical that you install the cam caps in their designated places.