Name: Yella Terra Holden/Buick Series 2 3800 L67 Ultralite 1.7:1 5/16in Shaft Roller Rockers — YT 6649
Brand: Yella Terra
SKU: YT 6649
Price: 900.00 AUD
Availability: InStock

Yella Terra YT 6649 Series 2 3800 L67 Ultralite shaft roller rockers

Yella Terra Holden/Buick Series 2 3800 L67 Ultralite 1.7:1 5/16in Shaft Roller Rockers — YT 6649

$900.00

Yella Terra’s Ultralite shaft and pedestal roller rocker system is a bolt-on hydraulic valvetrain upgrade for Series II 3.8L 3800 engines including the Holden L67 supercharged V6. This set uses a 1.7:1 rocker ratio with 5/16-inch mounting hardware and a common-shaft layout.

Ultralite construction

Supplier-rated to approximately 380 lb maximum open spring pressure for this application.
Set of 12 full-roller aluminium rocker arms.
Approximately 50% less oscillating nose weight than the factory rocker arrangement, supporting greater RPM potential and improved valve-float control.
Oversize full-complement caged bearings are designed for oscillating rocker loads.
Oversize precision-ground trunnions reduce friction and improve bearing support.
Aircraft-grade extruded aluminium arms improve strength-to-weight ratio and dissipate top-end heat.
Hardened and ground chromoly roller tips reduce valve-tip and guide wear.
Common-shaft mounting increases the clamping footprint without cylinder-head machining for the standard installation.
Fits beneath the factory rocker covers.

Important pushrod requirement

Yella Terra specifies its matching pushrods, part number YT 14103-12, sold separately. Pushrod length should still be measured and verified as part of the hydraulic rocker setup.

Technical specification

Rocker ratio: 1.7:1.
Mounting: bolt-on single shaft / pedestal system.
Mounting hardware: 5/16 in.
Operation: hydraulic.
Maximum spring diameter: 1.437 in.
Shims included: no.
Quantity: set of 12.

Installation: Always verify rocker geometry, pushrod length, retainer/spring clearance and piston-to-valve clearance for the complete camshaft and cylinder-head combination.