T&D Machine Engine Rocker Arm and Shaft Assembly

T&D Machine: The Standard in Shaft-Mount Rocker Arm & Shaft Assemblies

When serious engine builders and professional racers need a rocker arm and shaft assembly they can trust under the most brutal conditions, they turn to T&D Machine. T&D Machine is the leading manufacturer of high-performance shaft-mount rocker arm systems, and their Engine Rocker Arm and Shaft Assemblies represent the pinnacle of that expertise — engineered from the ground up for accuracy, durability, and maximum power transfer.

Two Material Paths, One Level of Excellence

T&D's rocker arm and shaft assemblies are offered in two primary material configurations, each suited to specific performance demands.

• Aluminum Shaft-Mount Systems: T&D aluminum shaft-mount roller rockers offer strength, accuracy, and performance in a light and optional ultra-lightweight configuration, designed primarily for race applications using the finest 2024 aluminum for tensile and yield strength. These CNC-machined rockers feature intricate oil galleries built in to direct oil from the pushrod to the shaft bearings and onto the roller tip.
• Steel Shaft-Mount Systems: T&D steel shaft-mount rockers are engineered for applications with more extreme cylinder pressures and longer duration use, using a proprietary chrome-moly construction that minimizes flex and valve train distortion — while still being designed to minimize weight with the highest strength on the market.

Built for an Enormous Range of Applications

T&D performance shaft-mount rocker arm systems are available for over 400 types of cylinder heads with a wide range of offsets and ratios. Whether you're running OEM iron heads, popular aftermarket castings, or a fully custom cylinder head, there is very likely a T&D assembly engineered specifically for your combination. T&D rockers are available on a build-to-order basis for proper performance and reliability, and custom rocker arm systems for specialty cylinder heads and customized valve positioning are available by special order.

Thoughtful Engineering Details That Matter

The difference between T&D and lesser alternatives shows up in the fine details. Adjuster screws are 7/16" and broached for a 3/16" socket to eliminate twisted Allen wrenches, while deep, case-hardened 8620 steel shafts are tempered for strength. For high-endurance applications, T&D's spring oil hole option uses a strategically placed .040" hole that intersects between the two bearings of the rocker arm, channeling oil precisely to the valve springs throughout the entire lift cycle. Rocker arm geometry is critical to valvetrain stability, durability, and accuracy — and T&D rocker assemblies include detailed instructions, a shaft height tool, and a mock-up pushrod (upon request) to easily achieve the correct geometry.

A Legacy Earned on the Race Track

In the early 1980s, GM's Buick Division recognized that the T&D shaft rocker system would be a key element for their V-6 engine program that came to have a major impact on NHRA drag racing, the Indy 500, and NASCAR competition. That race-proven heritage carries directly into every rocker arm and shaft assembly T&D produces today. T&D manufactures rocker arm systems for over 400 cylinder heads, and its products have established a reputation for the highest levels of quality, performance, and long-term reliability.