Cold morning warm days. Fall in Texas. Pulled into work one morning and pulled my jacket out of the rear trunk. WoW. It was toasty warm in the trunk and got me to thinking.

It's just the largest Heat Exchanger you can ask for. What about running a hose with a small inline fan through the targa clip cups down to the cabin heat inlet and pulling heat from the rear trunk and into the cabin??




Your ideas on how to make this work please.

Conceptually it might work, but it would be so inefficient that you'd drive a 100 miles before maybe feeling any heat in the cabin.

How about simply wrapping soft copper tubing around the exhaust pipes and then tapping them into the inputs in the engine bay?

I thought every 914 owner knew ...


Hot food goes in the rear and cold food goes up front

Simply put, purchase the low end Cool Shirt model with the ice chest exchanger that has a pump. Fill it with your favorite liquid media and run another set of tubes out to the trunk and create another separate circuit. Use circle and snake patterns to fully enclose the area. Take an old poly-fill jacket you might find at GoodWill or similar and make a heat blanket to cover or encapsulate the fluid lines.

Don the vest, turn on the pump, voila!

I agree it probably isn't terribly efficient, and you would also need to be concerned about carbon monoxide probably. I don't know about you but my rear trunk isnt air tight.

Good point.

Front trunk cooler....

Take some 3" flexible aluminum tubing and wrap it around the engine. Then stick a fan to it into the cabin.

any teener needs to be concerned about that. those heat exchangers are wrapped around exhaust pipes. I posted this before but any pilot shop, Aircraft Spruce, etc., sell a carbon monoxide stick-on monitor for less than $15. our cars are not well sealed and that probably works in our favor. if mine were a DD in a cold climate I would have a detector on my dash. smart pilots fly with a detector. it's a sneaky killer.

I agree with you Kent. As it is, the heating systems on air-cooled vehicles (at least Porsche & VW) leave a lot to be desired.

Aside from the heat exchanger arrangement (which could be deadly if there are any holes in the exhaust system), sucking 'fresh' air from the engine compartment isn't all that great either. Any oil seepage that gets cooked ends up in your lungs as well.

The flexible metal hose/ducting actually sounds like a viable alternative. Fresh air sucked from inside the passenger compartment ducted near the exhaust system and ducted through the rear trunk then back into the passenger compartment should eliminate most of the of the CO dangers.

Installing an electric heater would be a more preferable method and will provide you with fairly instant heat. You'd be wise to increase the alternator's amperage if you install a 300~600W ceramic-core heater.

A 300W heater will draw 23~25 amps, 600W will draw 45~50 amps ... pretty hard on the stock 55 amp alternator



For air conditioning, duct fresh air from the passenger compartment into an ice chest in the front trunk, then duct back into the passenger compartment. Refresh with new ice as needed.