Here is a better explanation...
Here is a better explanation of where the shims go. The lash adjusters (lifters) drop into these holes. Without the shim in place, there wouldn’t be enough preload, if any. The shims will raise the height of the lash adjuster so proper preload can be attained.
Competing in the NMRA's Super 'Stang class, Beefcake enjoyed instant success. Knowing he was going to compete at every event, Justin knew he was the ideal candidate for the heads and cams. Beefcake's GT already served as a testbed for other performance products so his car was the perfect candidate.
The heads chosen for Beefcake's GT are RGR/JPC CNC Stage 1 units. The heads feature a RGR custom competition valve job, custom machining of the stock intake and exhaust valves, and new bronze valve guides, seals, locks, retainers, and springs. RGR/JPC has both Stage 1 and Stage 2 heads available, but for Beefcake's car, the Stage 1 heads were chosen for this test.
Using engine assembly lube,...
Using engine assembly lube, Brian dabs the lash adjusters before inserting them into the heads. Just like in a pushrod application, the followers (rockers) ride on the lash adjuster on one side and the valve head on the other. You can see Brian has also used engine assembly lube for the cam journals as well in preparation for the cams install.
To go along with improved cylinder heads, RGR/JPC offers cam grinds in both naturally aspirated and blower-specific applications. JPC calls them its Stage 1 N/A, and Stage 1 Blower grinds. Remember, with a Four-Valve engine, there are four cams—one for the exhaust, and one for the intake on each cylinder head. The Stage 1 blower grinds in Beefcake's engine feature 225 degrees of duration at 0.050 on the intake side and 235 degrees of duration on the exhaust side. Lift numbers come in at 0.470-inch on the intake, and 0.450-inch on the exhaust side. Justin says the lift numbers are stock, but the magic comes from the extended duration built into the cams. The increased duration keeps the valves open longer, which allows the engine to take in and exit more air than the stock cams.
Beefcake's GT received the blower grinds because his GT features a Vortech JT-Trim supercharger system, but before we give away any more information, let's get the install, which took place at Finish Line Performance in Milford, Ohio. Beefcake is such a valued customer that Finish Line Performance's website has a Beefcake's Corner page.
Brian has set the cams in...
Brian has set the cams in place on the heads. Remember, the cams are intake and exhaust specific. In other words, you can’t just take the cams and throw them on. You must make sure they are installed in their proper locations. The intake cam is on the inside, or top, and the exhaust cam is on the outside, or bottom. Before installing the cams, though, Brian makes sure to clean them of any debris. You don’t want anything on the cams when you install them. Any piece of debris can wipe out a cam so make sure to properly clean them before installing.
Horse Sense: If you are looking for one-stop shopping, JPC Racing offers an '11-'12 Mustang GT 500hp Top Dog package (Starting at $5,795.95), consisting of a JPC full exhaust, JPC/RGR CNC‘d heads and cams, a Boss intake, a JLT Performance cold-air intake, new head gaskets and head bolts, and a JPC-tuned SCT SF3 tuner.

Brian bolts the cam caps over...

Brian bolts the cam caps over the cams in the same arrangement as they came off. If you look back at the image of just the head, you’ll see the cam caps are already in place. They must be reinstalled on the same journal. Like the heads, the cam caps also have a specific torque sequence and specs.

Brian holds the cam while...

Brian holds the cam while he torques the cam sprocket to spec. The cam sprockets have a chain to keep them in time, and another chain running from the crank sprocket up to the exhaust cam sprocket.

Here’s a closer look at the...

Here’s a closer look at the cam sprockets, and the chain used to connect them and keep them in time. The exhaust cam sprocket is used to connect the timing chain to the crank sprocket, which you can also see on the crank snout.

Here you can see Brian is...

Here you can see Brian is attaching the driver-side timing chain. He lines up the timing marks on both the exhaust cam sprocket and crank sprocket to appropriate marks on the chain to make sure the engine will be perfectly timed upon start-up.

Just like the links in the...

Just like the links in the chains of your old GT, Mach 1, or Hutch Trick Star, the timing chain features a darkened link, while the cam sprocket has a mark on it. If you notice in this image there is an L and a R. From what we’ve gathered, these sprockets are interchangeable. Therefore, if you install one on the left side of the engine, you line up the darkened link to the L. If you install the sprocket on the passenger side, or right side, of the engine, you’d line up the darkened link with the R. There’s also a tensioner for the cam sprocket chains.

Here’s a shot of the crank...

Here’s a shot of the crank sprockets. The driver-side chain is on the inside while the passenger-side chain is on the outside. Much like a drive belt, the cam sprockets and timing chains only go on one way. They are not interchangeable.

Brian reinstalled the front...

Brian reinstalled the front cover at this point, using the factory gasket with a dab of silicone at the area of where the heads bolt to the block. The camshaft actuators are located on the front of the cams, while the cam sensors are located at the back of the cams. These actuators are responsible for the variable valve action of the TiVCT camshafts and valvetrain.

Now Brian bolts on Beefcake’s...

Now Brian bolts on Beefcake’s ATI balancer, water pump, cam covers, and engine harness. You can see the wiring for the camshaft actuators, coils, fuel injectors, and throttle body.

Brian reinstalls the Vortech...

Brian reinstalls the Vortech JT-Trim supercharger on the engine before raising it back up into the engine bay. Beefcake’s car was used for testing by Vortech for fitment and functionality. So far, no complaints from anyone involved with Beefcake’s ride when it comes to power delivery from the Vortech.
Here’s how Beefcake’s engine compartment looked when he competed in our King of the Street competition. We’re only going to report the horsepower the car made with this combo, as he made further changes to the combo before KOTS.