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Air conditioning flow

Heating and Ventilation

Vehicle Information: Model: Carrera; Year: 1985; Body Type: Coupe; Engine (type, size, modifications): H-6, 3.2, stock; Total Mileage: 120,000;

This is not a question, but a tip for all those who, like myself, live in areas where decent air conditioning is not only desired, but a necessity. I find that the problem with the a/c in these older 911's may not necessarily be a higher than normal discharge temp, but low airflow at the dashboard registers. There is a floor discharge outlet right in front of the console that discharges cold air from the evaporator and diffuses it straight out onto the front seat occupant's calves. The problem with this set-up is that A: This air is coming directly from the evaporator housing and is at its coldest, so your legs get the coldest air while your upper torso and head feel the heat and humidity, and B: This vent acts like giant leak in the system, causing a large pressure drop downline at the dash registers. The result of this is low flow at the dash registers. To remedy this, I removed the diffuser, made a plug from a trimmed plastic spray paint can cap, pushed it into the duct, then re-installed the diffuser to keep it from popping out. I now have much better airflow at the dash registers, making my car much more enjoyable to drive on hot days, with no permanent modifications to the a/c system and at very minimal cost and effort.Please pass this on to other members. Thanks. Mike Masterson, Carolinas Region PCA.

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