You're ready for more. Your late-model Chevy handles great and has A/C, and your new wheels and tires look pretty cool too, but it still needs more power. It needs a performance cam to kick the level up a few notches. But to achieve the best performance from your computer-controlled car, everything must work in perfect harmony, blending horsepower, torque, driveability, and in most cases the ability to pass the state emissions test.
To realize the full benefit of a performance camshaft, you'll want to improve intake and exhaust flow and optimize the car's fuel management and computer systems to make that new camshaft come alive. When selecting your hot new bumpstick, remember to choose a cam that is designed for a computer-controlled system and will comply with >> your local emissions regulations. The onboard computer reacts to engine signals, such as manifold vacuum and the air/fuel mixture, which are mainly produced by valve timing. So it stands to reason that adding a camshaft not designed to work with these systems can cause driveability problems.
Factory replacement roller...
Factory replacement roller cams (top) are available in a variety of levels to wake up your small-block. For many applications, the original factory rollers can be retained to use with the new camshaft, but check with the manufacturer first. For earlier computer-controlled cars, performance flat-tappet hydraulic cams (bottom) enhance torque and horsepower.
For many late-model ('87-and-later) small-blocks, the factory has already fitted the block with a low-friction roller camshaft arrangement. So the good news is that replacing the stock low-lift unit with a hotter roller-hydraulic is relatively straightforward. For pre-'87 small-blocks, aftermarket cam manufacturers have plenty of flat-tappet designs engineered for early computer-controlled iron.
If you use your late-model as a daily driver (like most of us do), pay particular attention to the cam manufacturer's idle and powerband description. You'll want something that has a livable idle and low-to-midrange rpm band. Typically, these cams have 200-215 degrees duration at 0.050-inch lift. Once the duration begins to exceed that, manifold vacuum and low-speed power are exchanged for high-end power.
In this issue you'll find some proven modifications that will help enhance your new camshaft's performance, and most of them are easy to install in a few hours or over a weekend.
This '94 LT1's performance...
This '94 LT1's performance has been raised with a GM Performance Parts hydraulic roller (PN 12370845). The cam specs out at 0.520/0.546-inch lift with 1.6:1 roller rockers and 214/224 degrees duration at 0.050-inch lift.
If you're adding a new camshaft,...
If you're adding a new camshaft, you'll want to replace the factory exhaust system to gain even more power. These Edelbrock headers install easily and are 50-state legal.
The 350 in this '87 Camaro...
The 350 in this '87 Camaro is fitted with a Crane CompuCam roller stick that includes a California Air Resources Board Executive Order that makes it 50-state legal. The camshaft specs out at 214/220 degrees duration at 0.050-inch lift and 0.452/0.465-inch lift with a 112-degree lobe separation.
For earlier computer-controlled...
For earlier computer-controlled engines, you'll want to replace the computer chip with one such as this Jet Performance piece that allows the computer to enhance the added power potential the new camshaft delivers.
Later-model computer-controlled...
Later-model computer-controlled systems can be reprogrammed to optimize power from a new camshaft with the Hypertech Power Programmer III. Custom applications are also available from tuners and reprogrammers such as the Power Loader from Steve Cole's TTS Power Systems.
When you're done, be prepared...
When you're done, be prepared for some real fun blasting down your favorite stretch of road.