I came across an idea the other day that I think would be cool to share with other owners. I noticed how weak the heater air flow was in my 73 2.0, so I got one of the V-shaped ducts to shoot more air over to the passenger side, to no avail, so I thought, why not a separate fan?
The more I thought about the idea, the more I wanted to do it. The first thing I did was go to a local junkyard and found a 914 heater fan, the one that mounts inside the engine. Then I had to rebuild it, not too hard, just had to clean up the contacts a bit. Then I went down to the local Pep Boys and bought three and a half feet of heater hose. This stuff is only about a dollar a foot.
I took the factory end cap off the heater attachment inside the engine bay on the right side, then installed the hose with a hose clamp on to the attachment. I then mounted the fan with some plumbers tape to the pillar that holds up the grill on the right side of the engine lid, this may take some fitting to make sure that the lid closes right. Also, VERY important before you mount it, make sure you mount a rubber spacer or some other insulator against the fan housing and the pillar, otherwise it will short circuit as you turn on the fan.
Next, mount the hose to the end of the fan. Try to get the factory connector , or you will have to construct a suitable fitting. Next take the connections to the stock fan, the one that's already there, and splice the two wires to the wires on the new fan, be sure to solder and use twist caps.
Now test your fan. You should have A HUGE difference in the amount of air coming out of the vents. If your fan didn't come on, check the fuse in the relay board, (8 amp), then check the connection in the center tunnel.
I've done three of these conversions, and in each one, the spade on the switch needed to be cleaned. In closing, this only cost me about $15, and made my defroster churn out huge amounts of air. It's also really simple, and makes me wonder why Porsche didn't do it in the first place. Well I hope this helps out. Thanks for such a great web site, and I'll try to send some pictures as soon as I can.
Jared Fenton 73' 2.0