Premium Modified, Ported, and Calibrated Throttle Bodies. For 5.5L V8 engines (LT6).Corvette 8, Z06 (2023+).Please note: Only sold as a pair. Enhanced Performance Replacement for P/N: 12713793, 12729502.1 YEAR WARRANTY*. NEW option: 2 brand new reworked parts (0 miles / BNIB). FEATURES:• Optimized Active Contours with sonic flow nozzles• Porting Taper and Upstream Bore with Velocity Stack• Greater Discharge Coefficient of Plate/Blade interface• 16 Ra Microinch, Diamond Polished Surface Finish • Self-Cleaning Throat/Flow Gap BENEFITS:• Lower weight to power ratio at part throttle, for a more nimble/spirited driving experience • Linearization and smoothing of the curve for a more predictable response and crisper shifts• Immediate response right off idling while keeping idling function undisturbed (No Hesitation/Stumble)• Does not require tuning. Warranty safe.• More air/power at every single throttle position after idle. Crucial for starting or expanding power gain modifications