AEM Intercoolers are designed to significantly reduce inlet air temperature and provide more volume than the stock intercooler. AEM Intercoolers are designed using CFD and flow data and usually have an extra port in the intercooler discharge tube for auxiliary devices like boost pressure sensor, temp probe or water injection nozzles. Check your state laws for legality of water injection on your car. 2102-A and 2102-B are designed as a kit and must be used together. Use of one without the other voids the warranty.