[dfink]

Probably depends on the year of your car. My 85 has footwell blowers that don't work but I still get very good defrost. Bottom two levers on the dash to the right and both floor levers all the way up. System heats up faster that any water cooled car I have. My 85 also has the heater blower in the engine department. This blower does work on mine but when it was broken the defrost didn't work very well at idle. If the rear blower doesn't work or motor is bad do a search there several articles on how to convert the motor as they are no longer made new. If I turn on the top lever (fresh air) the velocity of the air coming out increases but the temp goes down so far defrosting doesn't work.