The Two-Valve Intake Market Continues To Diversify Itself As TFS Enters With A Sleek, New Manifold.
Dez Racing's Brian Machie (right) and Mike Dezotell (left) handled the installation and dyno testing of the TFS Two-Valve intake manifold.
Choosing the right combination is critical in building an efficient engine combination. The old clich that bigger is better has been thrown around over and over, and by now, everyone knows that a big camshaft combined with the largest heads may produce the most horsepower on a track engine, but will it remain street-worthy?
Probably not, but finding the right combination of parts has become easier these days as the aftermarket offers various camshaft grinds to meet the needs of the engine as well as an assortment of intakes and cylinder heads. For the 5.0L crowd, there are dozens of intakes and cylinder heads from which to choose, giving that segment virtually limitless amounts of combinations. However, there isn't a one-part-fits-all application. The Two-Valve modular engine market isn't as fortunate to have as many choices as its pushrod brethren, but the mod-motor crowd does have options to help fit their goals.
TFS announced its development of a Two-Valve intake last year, and we saw a production piece at the '06 PRI show. After some delays, we finally got our hands on one and put it through its paces.
Over the past two years, the aftermarket has responded to the great need of induction solutions for the Two-Valve engines. We still rely on various stages of porting with the stock heads, but the choices of intake manifolds are greatly increasing. The stock heads seem to respond well to porting, but the stock intake manifold, often times slightly aided with a larger upper plenum and a bigger throttle body, has hampered its potential. A Bullitt intake manifold works OK, and porting it helps the situation, but there's still room for improvement.
Today, the market is far from its dismal status two years ago as we have counted seven intakes with more on the horizon. Each of these manifolds are designed for a different type of combination, so you can go from mild to wild. Some testing of milder intakes has proven to be not so effective in power production versus cost. Others served their purpose quite well, helping free up serious airflow to the hungry intake ports.
Keith Johnson's '00 Mustang GT is the test subject, and its combination is fairly simple. Baseline power is placed at 441 rwhp and 413 rwtq-not bad for a pump gas-ingesting Two-Valve modular engine. It benefits from AFM Two-Valve camshafts, a ProCharger P1SC (12 psi), a TFS upper plenum, a BBK 70mm throttle body, and Bassani's complete exhaust setup with shorty headers. Naturally, Dezotell added a custom tune to the computer to make sure the fuel and timing were perfect for this street machine. | 
Brian Machie had to remove a lot of little things in order to swap the intake. Here, he pulls off the upper radiator hose. | 
The alternator is removed and relocated to make room for the front of the intake manifold. |
Once the blower, alternator, fuel rails, and other associated equipment are removed, it's time to start unbolting the intake manifold. Be careful when disconnecting the heater hoses as the fitting on the firewall can break. | 
A new heater hose is run under the manifold. | 
Dezotell had the P1SC blower set to 12 psi and used a Reichard Racing upper pulley. The shop also added a race by-pass valve when installing the supercharger system to eliminate blower surge on engine deceleration. Dezotell has encountered belt issues in the past when he jumped up the boost, and the larger by-pass valve helped cure the problem. |