I just got my full set of up-derfixen from the PCA...

Anyways...there was a great simple article about making the heat more efficient...

The reccomended lots of things, including filling the longs with foam beads....

The three I think are good for the 914

1) Wrap the heater tubes with duct insulation, there are two in the engine bay, one from each heat exchanger to the tube.
There are two in the trunk, up front...just paper.

2) Put a complete cover, except the gas tank filler, over the entire area between the struts and the dash.
Basically you are covering it up so no fresh air can get into the dash.

3) remove the fresh air boxand put a plastic cover on it for the winter...

Rich

2)

Granted, it rarely gets below freezing where I live, but I've never had a 914 (or any Porsche) that didn't have enough heat to allow running with the top off on the coldest of days. Takes a few minutes, but it's there. In fact, my old 911 powered bus had enough heat that you HAD to run with the windows partially open. That's "Up-fixen der Porsche", BTW. The Cap'n

I have the books right here, but didnt even bother to read the correct title...sorry.

In my part of the country, it gets really cold..

The part about the plastic over the fresh air box, and the hood over the area in the trunk does work...

I get alot of cold air through the vent that is under the dash pointing straight down...our beetle has the same problem...

On the beetle, we disconnected the fresh air lines from the system...fixed that....but the hood cover thing will wix all the rest of the cold air that comes in through the dash....

Just thought some of the other cold weather drivers might like to have draft free driving for a change..

Rich

QUOTE (r_towle @ Nov 12 2005, 07:05 PM)

1) Wrap the heater tubes with duct insulation, there are two in the engine bay, one from each heat exchanger to the tube. There are two in the trunk, up front...just paper.

It would seem that the steel heat exchanger exterior would also cool the heat exchanged air as the car passes through the cold winter air. I've seen engine header tubes wrapped with insulation tape. Is it possible to wrap the heat exchangers with insulation tape? Or would this promote rusting?

Spoke

the article went in serious detail....they sent a car to a company in minnesota to study the possible upgrade...had meters looking at heat loss...

They concluded that it was not an issue of the heater boxes design...that was fine...but the issue was really two fold.

Air leaks in the cabin
Insulating the heating tubes coming from the back of the car.

The car is blowing air at around 270 degrees once it leaves the heater boxes, more than enough...problem is (according to these guys) there is a 10 degree per foot loss of heat in un insulated tubes..

Then you add in the fresh air which is blowing in COLD air into the defroster and heater circuit and the heat loss is amazing...

Rich