16 AN thermostat housing for GM LS based engines makes plumbing an engine coolant system a breeze. Our -16 AN thermostat housing allows you to retain a factory thermostat, where others don't! Any fuel injected engine relies on engine coolant temperature for certain computer functions. Therefore we saw it necessary to retain the thermostat.
By using AN fittings it takes the guess work out of what coolant hose can I fit. It also eliminates the need of buying 2 or 3 hoses just to make one work. The extremely clean appearance and simplicity of service are an added bonus.