The latest Lunati asymmetrical camshafts, the new TL2 and the TR2, designed for small- and big-block Chevrolet racing engines, are quite the marvels.
The TL denotes Lunati's cam series for solid flat tappets, while the TR designation represents solid roller tappets, and the number 2 stands for second generation. Both series of camshafts are designed using the latest technology and feature increased lobe lift—therefore greater valve lift.
Lunati's design begins at the first valve moment of the cycle, the exhaust opening point. By deliberately delaying the opening point they generate more torque from the power stroke, consequently adding more power to the crank. This process occurs throughout the rpm band and is effective as long as the exhaust gases can be properly scavenged from the chamber at high rpm.
Then, as you might expect, they open the intake valve before Top Dead Center. But they open it late to reduce the effects of reversion entering the intake port. They also open it fast, inducing earlier airflow and providing more high-lift area (also known as more area under the curve).
This occurs after TDC as the piston heads downward on its intake stroke, which creates high velocity in the port. If a port has high velocity and the intake valve has lots of high-lift area, the port fills the cylinder faster and has more time to fill it—thus increasing the engine's potential horsepower and torque.
They then close the intake valve gently to prevent valve bounce and facilitate valvetrain reliability. Of the four timing points, the exhaust closing point has the least power-producing effect on the valvetrain. Yet in this area Lunati exercises special care to ensure exhaust-valve reliability.
These cams are specifically developed for short track Modified applications, Dirt Late Models, Sprint Cars, as well as drag and street/strip vehicles. Depending on valvetrain weight, these new TL2 and TR2 camshafts provide stability up to 8,800 rpm. Included in its 30 new part numbers, Lunati has introduced smaller base circle designs that provide extra clearance in stroker engines.
TL2 prices start at $187.06 and TR2 at $337.16 with custom grinds available as well.