Product Description
Michigan Motorsports Billet Rocker Stand Pair for Cathedral Port Heads
Fits 1997–2013 LS-Based 4.8L, 5.3L, 5.7L & 1999–2006 6.0L Engines | Replaces GM 12552203
The Michigan Motorsports Billet Rocker Stand Pair is a precision-engineered upgrade for GM LS cathedral port cylinder heads, designed to dramatically improve valvetrain stability and consistency over factory cast stands. CNC machined in the USA from 6061 billet aluminum, these rocker stands reduce flex and eliminate the dimensional inconsistencies commonly found in OEM GM stands. Factory stands can vary as much as .015", making accurate lifter preload difficult—especially with short-travel aftermarket lifters. Michigan Motorsports billet stands are held true within .001" across their full length, ensuring precise rocker geometry and reliable valvetrain performance in both stock rebuilds and performance applications.
Key Features & Benefits
- Improves Valvetrain Rigidity & Stability: Billet aluminum construction significantly reduces flex compared to OEM cast stands, maintaining consistent rocker arm geometry under load.
- Precise Rocker Saddle Height Control: Machined true within .001" across the entire stand length, eliminating the .015" variance commonly seen in factory GM stands.
- Ideal for Aftermarket Lifter Setups: Consistent rocker height makes setting correct lifter preload far easier, especially when using short-travel performance lifters.
- Direct Replacement for OEM Stands: Replaces GM part number 12552203 with no modification required for compatible cathedral port LS cylinder heads.
- Made in the USA from 6061 Billet Aluminum: CNC machined from high-strength 6061 aluminum for long-term durability and precision fitment.
Key Fitments
- LS-Based Cathedral Port Engines: 1997–2013 4.8L & 5.3L, 1997–2013 5.7L, and 1999–2006 6.0L
- Engine Codes: LS1, LS6, LS2, LR4, L20, LY2, LM7, LC9, LM4, LS4, L33, L59, LH6, LY5, LMG, LMF, LQ4, LQ9
- Not Compatible With: 2007–newer 6.0L engines and all 6.2L engines
