The 2022+ Honda Civic Si arrives from the factory with a turbocharged 1.5T that is well-sorted for daily driving, but the stock induction, charge cooling, and thermal management systems all leave room on the table. The Mishimoto Ultimate Bundle addresses each of those areas with six purpose-built upgrades designed to work together as a complete system.

The Performance Air Intake is the first upgrade in the induction path, removing 50.7% of the restriction found in the factory intake. The result is more responsive throttle input, a sharper induction note under acceleration, and dyno-proven gains of up to 4.9 HP and 4.7 lb-ft of torque. The injection-molded MAF housing integrates directly with the stock system, and the included high-flow oiled air filter keeps filtration quality high without sacrificing airflow.

From there, charge air passes through a significantly upgraded cooling system. The Performance Intercooler replaces the factory unit with a bar-and-plate core that increases core volume by 146% and drops average outlet air temperatures by 18.1°F compared to stock. Lower charge temperatures mean more consistent power delivery and less ECU intervention during sustained hard driving. The intercooler is built with cast aluminum end tanks and welded construction rated to support builds up to 572 HP. Paired with it, the Performance Intercooler Pipe Kit replaces the restrictive factory piping with high-flow aluminum pipes that increase hot-side flow area by 103% and cold-side by 75%, unlocking an additional five horsepower over the intercooler alone. The OEM resonator is eliminated in the process, sharpening the induction sound under boost. Five-layer DuraCore silicone couplers and a pre-drilled 1/8" NPT sensor port on the cold-side pipe round out the kit.

Alongside the performance upgrades, three components work to protect the engine and cooling system over the long term. The Baffled Oil Catch Can mounts in-line with the PCV system and uses a 50-micron bronze filter and internal air diverter baffle to separate oil particles from blow-by gases before they can reach the intake valves and combustion chamber. Left unchecked, that oil contamination leads to carbon buildup and reduced octane quality in direct-injection engines like the L15. The can installs in under thirty minutes at a firewall-mounted location that keeps it accessible for regular service.

The Silicone Coolant Hose Kit replaces the factory rubber hoses with a five-layer silicone construction reinforced with heat-resistant embedded fibers. The full kit (upper hose, lower hose, and reservoir hose) bolts directly into the stock locations with the included worm-gear clamps, improving pressure and heat tolerance throughout the cooling circuit. The Performance Aluminum Radiator completes the thermal management system with a fully aluminum core featuring precision TIG-welded end tanks and a 40mm strutted tube design. Core volume increases by 44% and internal tube area by 85% over stock, giving the cooling system the capacity to keep up under demanding conditions. A magnetic drain plug is included to capture metallic particles in the coolant before they can cause wear.

All six components are direct-fit for the 2022+ Civic Si, install without bumper removal or permanent modifications, and are backed by the Mishimoto Lifetime Warranty.