For those with electronic fuel injection (EFI) cars, there has been a void of camshaft choices specifically designed for modern, EFI engines. To address this issue, the engineers of COMP Cams® and FAST™ joined forces to design a line of camshafts specifically for both OE and aftermarket controlled EFI engines.
EFI engines have very different requirements than those of carbureted engines, which require a strong signal at the carburetor booster to draw the correct fuel mixture into the combustion chamber. EFI engines do not require that excess signal, so camshaft lobes can be manipulated for increased performance and that’s exactly what FAST™ and COMP engineers have done.
With the introduction of the Xtreme Fuel Injection (XFI™) line of camshafts, these engineers addressed the specific needs of EFI engines. The cams were created to provide the optimum power upgrade in a wide range of fuel injected applications.
 COMP Cams® offers an extensive line-up of Ford 3v camshafts |
To check out how the XFI™ cam performs, a cam and valve spring swap was set up at COMP Cams® R & D facility. This project had two objectives. The first was to provide a full step-by-step demonstration of a cam installation process in a selected EFI engine. The second was to validate the power increase as the result of a cam exchange.
The EFI-optimized cam demonstration was performed on a 2005 Mustang GT. It is equipped with a 4.6-liter 3 Valve Modular Overhead Cam Engine and the cam to be installed is the XFI™ Ford Modular 3 Valve Camshaft, along with Beehive™ Springs and retainers. A baseline point of reference for power output was required, so a baseline reading of horsepower and torque was made on the COMP SuperFlow chassis dyno. When the installation was complete, another dyno run was taken for comparison to demonstrate the power output difference provided by the new cams.
COMP Cams® Ford Modular Installation Instructions XFI™ Ford 3V Cam Specs, Dyno Sheets, Testing Video, Etc Email CAM HELP™ For A Cam Recommendation Download CamQuest Cam Selection Software Contact:
COMP Cams®
3406 Democrat Rd.
Memphis, TN 38118
(901)795-2400
CAM HELP™ 1-800-999-0853
www.compcams.com 
This project is being conducted on a 2005 Ford 3v Mustang; many of the procedures are similar in other applications.
It’s important, however, to look at each application to develop a step-by-step installation plan. There is no substitute for
a well organized install procedure.
To clear the upper and side areas for access to the valve covers that house the overhead cams, the first step is to
disconnect the battery cables, take out the battery, remove the battery tray, and disconnect the air tube coming into
the throttle body.
This Mustang GT is equipped with a
ZEX™ Nitrous System and it has to be disconnected. TIP: When the nitrous
system is disconnected, it’s very important to seal off the open ends. This prevents fuel from leaking as well as
preventing debris from getting into the system.
Next the cam synchronization sensor is removed and the harness is disconnected. TIP: Make sure the plugs are
covered and clear of the work area to prevent incidental debris or oil contact. This simple procedure will ensure
plugs are clean and will function correctly when they are reconnected.
With the working area clear of all obstructions, the spring and cam swap begins. To start this process, the spark
plug coil modules are taken out so the valve covers and spark plugs can be removed.
Now the valve covers are removed. TIP: When the valve covers have been removed, it’s a good idea to have some
clean shop rags handy to use as a cover to prevent debris or small parts from getting into the engine through the
drain back holes. This is a small action but it has huge benefits, because any parts or debris that gets in will not
lead to a good result.
Next, a reference mark is made on the timing chain. If for any reason the chain or gear loosens, this mark becomes
a reference point.
Now the cam is rotated to bring the follower to the base circle of the lobe in preparation for removing them. This step
takes the pressure off the follower and provides more room to maneuver them out of the engine.
Next, the roller followers are removed. This step is accomplished with the use of a specially adapted compression
tool shown here. With the spring compressed, the follower is removed in preparation for the valve spring exchange.
The stock followers will be reused when the cam swap takes place. The stock roller followers are strong and durable.
They are reused when the new cams are installed. TIP: The caps are stamped with numbers and arrows for easy
replacement reference. The number refers to its location on the head and the arrow points to the front of the motor.
Spark plugs are removed one cylinder at a time. As each is removed a special valve compression adapter fitting
is put in place and the cylinder is subjected to compressed air that holds the valves closed when the valve springs
are removed. Approximately 100 lbs of pressure applied to the cylinder will do the job of holding the valves closed.
Next, the stock locks, retainers, and springs are taken out and the new Beehive™ Springs (Part
#26113-24) and
retainers (Part #791-24) are installed using the special spring compression tool.
The stock locks are used in the spring swap. TIP: When replacing the locks, it’s a good idea to put a thin coating of
cam lube on the inside of the locks. This will help hold them in place during the spring installation.
With the spring swap complete, the cam swap process begins with the insertion of a specialized wedge tool. It
is inserted behind the front timing cover and works as a wedge against the bottom side of the timing chain where
the tensioner guide is located. This pressure holds the chain in place, and the cam can be removed without taking
the front timing cover off, which saves a substantial amount of time.
The next step is the removal of the cam caps. TIP: At this point the cam bolt should be loosened before removing
the caps. This will allow the cam and gears to be removed next.
With the cam caps removed it’s now time for the new cams (Part
#127300) to be placed in the engine. Before the
cams are put in place, the application of
cam lube is required. TIP: Make sure you have lubed the cam properly.
TIP: In the case of the Ford Modular 3 valve engine, the cams are different lengths due to the cylinder offset in this
engine. The cam with the longer snout, shown here, goes to the driver’s side of the engine.
Now the cams are placed in the engine. TIP: The cams each have a slotted keyway which prevents any incorrect fit
to the timing chain.
TIP: When placing the cam and replacing the valve covers, it’s very important to avoid contact with the variable
cam timing solenoid (VCT) shown here. Damage to the VCT will create a headache you don’t want.
With the cam installed, the cam caps are torqued in place, the followers are reinstalled and the valve covers are
put back in place. TIP: Make sure the caps are properly lubricated.
COMP Cams® Ford Modular Installation Instructions XFI™ Ford 3V Cam Specs, Dyno Sheets, Testing Video, Etc Email CAM HELP™ For A Cam Recommendation Download CamQuest Cam Selection Software
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