Pete Epple Technical Editor
April 1, 2010

An internal combustion engine is essentially an air pump, hence, the amount of power an engine produces is based on how much air you can efficiently move through it. Although intake manifolds, cylinder heads, and exhaust systems play a very important part, without a way to control airflow in and out of the cylinders, they are rendered useless.

Camshafts play a huge role when it comes to making power. When it all boils down, the camshaft(s) orchestrate a symphony of valvetrain components that allow the air/fuel mixture in, and spent exhaust gasses out. Camshafts are measured in a few different areas-lift, duration, lobe separation angle, and intake and exhaust centerlines. Each specification helps to make up a cam profile. Though we could go on for days about everything that makes a cam work, for this story we are going to stick to the basics.

Lift is probably the most commonly known measurement when talking about a camshaft. It's simply how far the cam allows the valve to rise off the valve seat.

Duration is the measurement of how long the valve remains off the seat. Duration will tend to dictate an engine's personality. If the valves stay open for a longer period of time, overlap generally increases, which is good for high-rpm power but bad for emissions and idle quality. Overlap is when both the intake and exhaust valves are open simultaneously, and is another way engine builders can improve scavenging.

Lobe separation angle (LSA) is the distance between an intake lobe and exhaust lobe at its respective max lift point. LSA is directly related to overlap and also helps with scavenging. If a camshaft has a wider LSA (higher numerical number), there will be less overlap. This offers more idle vacuum because there is less cylinder pressure bleed off as the piston approaches BDC. As the LSA tightens (lower numerical number), intake manifold vacuum will be decreased.

Intake and exhaust centerlines are ground into the camshaft as initial timing points, and give engines builders the ability to degree the camshaft(s) to the rotating assembly.

The Hardware
To put this camshaft theory into practice, we headed to Blow-By Racing (BBR) in Boca Raton, Florida, where Chris Jones and Matt Frith were preparing to swap camshafts in BBR's 2010 Mustang GT.

BBR's Billet Stage 1 camshafts are a considerable step up from the stock sticks. "We designed the BBR Stage 1 cams to be as aggressive as possible without having to change valvesprings," explains Jones. This speeds the install time and saves the customer money, yet provides a nice upgrade over stock in power and sound quality.

"On a stock Three-Valve Mustang, valvespring coil-bind occurs at 0.512-inch lift. Our Stage 1 cams have 0.480-inch lift. The other benefit of our Stage 1 cams is that they are designed to take advantage of the Variable Cam Timing from the factory."

With the stock cams checking in at 0.439/0.439-inch lift, the 0.480/0.480-inch lift BBR cams are a healthy improvement. Lift isn't the only area where BBR has made improvements. Duration has been bumped from 196/221 degrees at 0.050-inch lift to 227/233 at 0.050, and the LSA went from 115.5 degrees with the stock cams to 114 with BBR's Stage 1s.

Installation
Matt Frith, affectionately known around the shop as Googli Bear, started by strapping the Mustang to BBR's in-house Dynojet for baseline numbers. After a few quick pulls, the GT laid down 306 rwhp and 323 lb-ft of torque, and we headed to the track. After a few passes down the strip at Palm Beach International Raceway (PBIR), in Jupiter, Florida, Jones got the launch down and the Mustang clicked off consistent mid-13-second e.t.'s, with a best of 13.55 at over 104 mph.

Photo Gallery

View Photo Gallery

Back at the shop, Frith made quick work of draining all of the fluids in preparation for our cam swap. With the JLT cold-air intake, radiator cover, and electric fan removed, the front of the engine was easily accessible. Following the removal of the valve covers and the rest of the accessories, the front cover came off, exposing the timing chains. After removing the chains, the stock camshafts were ready to be removed. Once unbolted, the cams were removed, followed by the followers and lifters.

Although this 2010 has about 12,000 miles on the clock, this was the perfect opportunity to check the majority of the valvetrain before installing the new camshafts.

With the lifter and flowers lubed up and reinstalled, it was time for the new bump sticks to take up residence atop the cylinder heads. Frith made quick work of reinstalling the shafts and setting up the timing chains before bolting the front cover back on. Before we knew it, Jones was loading the custom SCT tune and getting ready for our second dyno session.

With the new tune loaded and the Mustang back at the same operating temperature as our first test, Jones spun the rollers to a healthy 340 rwhp with 327 lb-ft of torque. We were impressed to see a gain of 34 rwhp from a mild cam swap. Happy with our dyno results, it was time to head back to the track.

PBIR was again the backdrop for what should have been a nice evening of test and tune runs. Unfortunately, the weather was not on our side, and rain sidelined our test. We returned Saturday morning, and the National Sport Compact Racing Association was nice enough to let us make a few runs during the test-and-tune portion of its event. With the tire pressure set on our Mickey Thompson ET Street Radials, Jones rowed through the gears, this time laying down a much more respectable 13.00 at almost 107 mph.

BBR's 2010 Mustang GT responded very well to a simple cam swap. Its billet Stage 1 cams added 34 rwhp and helped drop quarter-mile times by over 0.5.

"With the cams it feels like a whole new car," explains Frith. "Throttle response and acceleration are night and day compared to before, and the car just feels more powerful. With the stock cams you use to feel the VCT advancing and retarding the cam timing, but that is almost completely gone now. Plus the choppy idle just sounds cool."

The addition of 34 rwhp and a more aggressive idle adds a touch of old-school muscle to the new-school hot rod.

The addition of 34 rwhp and a more aggressive idle adds a touch of old-school muscle to the new-school hot rod.

Photo Gallery

View Photo Gallery