Yella Terra Platinum Shaft Mount Roller Rockers – Ford Windsor Factory Iron Heads

Application

Designed specifically for Ford Windsor factory cast iron cylinder heads (carburetted applications).

 Suitable for:

• Factory 3/8" stud cylinder heads with slotted pushrod guide holes.
• Factory 3/8" stud cylinder heads with round pushrod holes.
• Factory 3/8" x 5/16" stepped stud cylinder heads.

Cylinder Head Preparation Required

 For installation, cylinder heads must be:

• Machined approximately 0.300"–0.320" (7.6–8.1mm) from the rocker mounting pads.
• Drilled and tapped to accept 7/16" mounting hardware.

 Platinum Race Series

Designed for strength and built to win, the Yella Terra Platinum Race Series represents the ultimate in valvetrain performance. Manufactured and assembled in Australia using premium materials sourced locally and from the USA, Platinum rockers are engineered for serious race and high-performance applications. Unlike conventional rocker systems, the Platinum range offers a wide selection of true rocker ratios, allowing increased valve lift without relying solely on aggressive camshaft profiles. This reduces lifter and pushrod inertia while maintaining excellent valvetrain stability at high engine speeds. The proven shaft-mount design utilises heavy-duty 7/16" and 10mm hardware to deliver exceptional rigidity, durability and reliability under the most demanding racing conditions.

 Features & Benefits

 Extreme Strength Construction

• Wide-body rocker arms extruded from aircraft-grade aluminium for maximum strength and resistance to deflection.
• Designed to withstand up to 900 lbs maximum open spring pressure*.
• Excellent heat dissipation properties help control top-end operating temperatures.

Premium Bearing & Trunnion System

• Oversize full-complement caged bearings specifically designed for oscillating rocker loads.
• Precision-ground oversized trunnions minimise friction and maximise durability.

CNC-Machined Precision

• Intricately balanced CNC-machined rocker arms promote superior valvetrain stability.
• Engineered to maintain valvetrain harmony at high RPM.

Proven Shaft-Mount Stability

• Common shaft design supports both intake and exhaust rockers, effectively doubling the clamping footprint.
• Provides significantly greater stability than conventional stud-mounted systems.
• No additional cylinder head modifications required beyond standard installation machining.

Multiple Ratio Options

• Available in various rocker ratios to suit a wide range of camshaft profiles.
• Higher ratios can increase valve lift on both factory and aftermarket camshafts without changing the camshaft itself.

Premium Roller Tip Design

• Hardened and precision-ground chrome molybdenum steel roller tips.
• Large-diameter roller tip positively retained via internal circlip.
• Reduces valve tip and valve guide wear.
• Promotes smoother, quieter operation.
• Helps maintain valve lash and reduces ongoing maintenance requirements.

Why Choose Yella Terra Platinum?

When maximum RPM capability, valvetrain stability and durability are critical, Yella Terra Platinum Shaft Mount Rockers deliver proven race-winning performance. Built from premium materials and backed by decades of Australian engineering, they remain the benchmark for serious Ford Windsor race engines.

*Maximum spring pressure rating is application dependent and subject to correct installation and valvetrain geometry.

Tech Spec