What size throttle body is a stock LSA?
The stock throttle body for the LSA is 90 millimeters in diameter.
The LSA is GM’s 6.2-liter supercharged V8 used in high-performance models like the CTS-V and Camaro ZL1. The factory intake system centers on a 90 mm bore that governs air entering the engine, and this size is a key reference point for enthusiasts considering upgrades or verification. This article explains the size, where it sits in the system, and what to know if you’re evaluating replacements or tuning.
Background: the LSA and why throttle body size matters
The LSA is a supercharged variant of GM’s small-block V8 family, tuned for peak power with forced induction. The throttle body controls the amount of air that can flow into the intake plenum and ultimately the combustion chambers. On the stock LSA configuration, the 90 mm bore is designed to work with the stock blower and intake setup to deliver factory performance targets. Changes to this size can affect throttle response, peak power, and the calibration required to run properly.
Stock size across key LSA applications
Before listing the applications, note that the factory configuration for the LSA’s throttle body is 90 mm across the main performance models that used this engine.
- CTS-V (2009–2013, with some market variations) — 90 mm throttle body
- Camaro ZL1 (2012–2015) — 90 mm throttle body
These major LSA-powered trims share the same 90 mm throttle body, reflecting GM’s engineering choice to standardize air intake for the blown 6.2L across different platforms. This size aligns with the engine’s boosted air demands at stock power levels and helps ensure consistent calibration across models.
Upgrading considerations
If you’re contemplating a larger throttle body to increase airflow, there are several important considerations beyond bore size.
Common aftermarket sizes and what to expect
Enthusiasts commonly explore 92 mm and 102 mm aftermarket options for LS-based engines. While these larger bores can increase potential airflow, the actual performance gains depend on supporting components such as the intake, intercooler efficiency, camshaft profile, and the tune.
- 92 mm and 102 mm throttle bodies are popular upgrade targets, but they require careful matching with the intake system and calibration.
- Simply swapping to a larger throttle body without other supporting upgrades often yields diminishing returns or can harm drivability.
In practice, the biggest gains come from a combination of better air intake, intercooler airflow, a suitable cam or valve train adjustments, and a tune that recalibrates MAF/fuel mappings to the new airflow characteristics.
Tuning and installation considerations
Upgrading the throttle body typically necessitates a tune to ensure the engine management system correctly accounts for the increased airflow. Other considerations include compatibility with the existing intake manifold, potential need for hardware adapters, and verifying the calibration for the mass air flow sensor and fuel delivery. Warranty implications may also apply when using non-GM parts or non-factory configurations.
How to verify your throttle body size
To confirm the stock size on a specific vehicle or to verify a replacement, use these checks.
- Inspect the bore diameter on the throttle body with a caliper or ruler to confirm the measurement.
- Look for a stamped part number on the throttle body housing and cross-check it against GM parts catalogs or the vehicle’s service manual.
- Consult the vehicle’s documentation or contact a GM dealer or reputable tuner with the VIN to verify factory specifications for that exact model year.
Accurate verification helps ensure any upgrade plans align with the actual hardware and the required calibration.
Summary
The factory throttle body on the LSA-powered CTS-V and Camaro ZL1 is 90 mm in diameter. While larger aftermarket options exist (commonly 92 mm or 102 mm), any gains depend on broader system upgrades and a proper tune. Verification of the exact part and compatibility is essential before making changes, as the intake, intercooler, and engine management all work together to deliver performance from the stock configuration.
