Due to a recent fast-andfurious month (that included getting a firsthand look-from the passenger's seat-at drifting in Tokyo, Japan), time constraints prevented us from taking on a bigger project for this issue's Tech Inspection. So, as our deadline loomed, we assembled the following photos and captions to take you through the super-simple install of CG-Lock ($41.95), a cool seatbelt-enhancement device that can help improve driving control and comfort when you're letting your Pony run.
The device was designed for weekend- warrior enthusiasts who aren't afraid to put their 'Stangs through a good workout on the dragstrip, autocross grid, road course, or even the drifting course every now and then but don't want or need a full harness in their rides. The CG-Lock (CG stands for "center of gravity") keeps your body's lower end from sliding around in the seat by literally locking the lap-belt portion of the factory safety restraint at the desired tightness.
It's important to have as little movement in the seat as possible, as maintaining good driving position and posture can increase your ability to react quickly to road or situation changes. The CG-Lock is a good alternative to a full safety harness, providing nearly 80 percent of the response and feel you get from a full race harness at a fraction of the cost.
Our friend Oscar Velez was kind enough to let us install a CG-Lock on his '04 Cobra. Oscar drives his snake everywhere, and like most hard-core 'Stang nuts, he cuts it loose on the dragstrip as well. CG-Lock is a cinch on many levels. It's a cinch to install (we had it in place in less than 10 minutes), it's a cinch to operate. Once you pull up on the shoulder harness to tighten the lap belt, the CG-Lock will cinch you down into the seat and hold you there until the ride is over.
First and foremost, OEM passive safety restraints (seatbelts) prevent occupants from being injured in the event of an accident. From a performance-driving standpoint, however, an overabundance of slack in the lap belt (which is an inherent trait of the factory restraints on all vehicles) is not good. | 
This is CG-Lock's lower clamping plate. When tightened, these grooves dig into a seatbelt buckle's heel and secure the plate to the buckle. | 
The CG-Lock is clamped on the rear (heel) section of the seatbelt buckle, directly behind the passthrough slot for the webbing. The capscrews are tightened until they're fully inside but don't protrude beyond the lower clamp plate. The CG-Lock can't be pulled off the buckle by hand (it should be tight enough to withstand 30 pounds of force). |
With the clamp plate secured, we remove the unit's slide cover and lay the shoulder-belt webbing across the top of the knurled roller that lies inside the CG-Lock's body. When this is done, the slide is reinstalled. Make sure the finger-grip bar on the slide is pointed toward the seatbelt's tongue. If it isn't, the cover must be turned around before trying to use the CG-Lock. Engaging and disengaging the device is as simple as pressing a small thumb lever downward (which releases the slide's grip on the webbing), then moving the slide either forward or backward in an even motion (follow the "On" and "Off" arrows). Detents on each side of the chassis prevent moving the cover too far. | 
Once the CG-Lock is engaged, pulling upward on the shoulder harness tightens the lap belt. The slack is gone, and the lap belt will maintain its tightness until it is manually released. The harder we pulled, the tighter the lap belt got. [Mustang & Fords Editor Mark Houlahan suggested we make an airplane seat extender joke here. It was a good idea, but if you've seen Mark, you'd think he was speaking from experience. -Ed] | 
The shoulder harness is unaffected by the CG-Lock, so arm and upper-body movement is normal when the lock is set. |