HEAT! Ideas for an aux heater in car w/o exchangers?

[Ringmaster]

I live in a cold part of the world and own an air-cooled Porsche that doesn't have heat exchangers on the headers
I won't drive this car in the snow or at temps below approx 20F, but even on sunny fall and spring mornings the temps can be in the 30s....too chilly for an enjoyable drive sans heat!

Has anyone found a simple solution for in cabin heat? I searched this site and found someone using a gas boat heater but it appeared to be a bit bulky and involved lots of custom fitting.

Perhaps something electric under the dash? What do small aircraft use?

Any ideas or advice would be appreciated.

[tharbert]

I don't know much about the alternatives but your question begs another. If you are going to go through the trouble and $$ of kludging together a heat source, why not go back to exhaust with H/E's? That way, you get heat for your defrosters too.

Also, what do you have now? A pic would be nice.

[Ringmaster]

Originally Posted by tharbert

I don't know much about the alternatives but your question begs another. If you are going to go through the trouble and $$ of kludging together a heat source, why not go back to exhaust with H/E's? That way, you get heat for your defrosters too.

Also, what do you have now? A pic would be nice.

No pics at the moment. It is a custom set of headers for twin turbos. It would be nearly impossible to add heaters boxes

[gestalt1]

how about adding seat warmers - i've seen a few upholstery shops advertising that they can add them. not sure if the alternator has enough output to run them however. the aux heaters that run off the cigarette lighter don't do much.

[HawgRyder]

Just thought of something....how much heat would be available from the front oil cooler?
It's up front....air goes through it...a fan would help in both heating and cooling...and a duct with a deflector could be easy.
Just wondering.
Bob

[Formerly Steve Wilkinson]

Small single-engine aircraft and many twins use heat exchangers--a muff around an exhaust pipe, just like 911s. Some light twins use gasoline heaters in the nose compartment. I've flown Piper Aztecs with gas heaters and I think Twin Comanches and Aero Commanders.

Didn't early 911s use gasoline heaters that fit into the smuggler's box?

[unclebilly]

I used to work with Canadian Electric Vehicles. They offer an electric heater... depending on the size of your alternator, this could be a good option for you...

http://www.canev.com/KitsComp/Components/Heater.html

Cally Randy, he'll tell you how many amps it draws.

[deathpunk dan]

Couldn't you have a good exhaust shop fab a heat exchanger box on the headers? I know Foley does this for their 914/912E headers.

[unclebilly]

Ok, forget that, it looks like it would be 125 amps... 1500 Watts / 36 volts = 41.7 amps but you are running 12 volts so 3 times 41.7 amps = 125 amps.

Maybe Randy knows of a less powerful 12 volt unit.

[pete3799]

Someone here put an Espar heater in the smugglers box (don't remember who)
Maybe a search will turn it up.

[Flyin Brian]

in Excellence a hot Rod 356 used an electric heater. Rally cars use them too. I don't know a brand, but a little research on rally prep shops may help. Looking forward to what u find out.

[pete3799]

Found it.Modern Eberspacher heater installation

[sc_rufctr]

I've seen a car in Aus that uses two 12v hair dryers to defrost the windshield.
It works really well but it wouldn't provide enough additional heat for the cabin.

Something mentioned earlier in this thread is using the oil cooler up front and ducting the air inside the cabin...

What if you took this one step further?

A dedicated oil cooler installed in the car under the dash that had a custom shroud and fan to blow cabin air through the cooler vains.
(You could have a by pass cock that would switch to the outside cooler in warmer weather)

You'd have to muck around with it until you had something that worked well...

But one problem that would be hard to overcome is the slowness of the oil to heat up to a point were you could get an acceptable amount of heat in the cabin.
How long does it take for a 911 to reach normal operating temperature in cold weather?

Maybe a customer made heat exchanger around the headers would be the better option.

[djpateman]

Any electric heater that is effective would require an alternator too large to be available to fit, or a second alternator in place of an AC compressor. The original gas heater that fits in the smugglers box was at best supplemental. The only useful source of heat is the exhaust pipes.

[gestalt1]

I found this for seat heaters, only draws 4 amps on the high setting. trying to heat the air volume of the 911 interior takes a lot more energy. seat heaters won't help the ears nose and fingers but you can wear a cap and gloves. the gas heaters do work, webasto was the original manufacturer that supplied the system in porsches. the big trouble is that they consume a lot of gas.

http://www.sportsimportsltd.com/carbon-fiber-seat-heater-kit.html

[Mattlock18]

When my heat went out last fall, I bought a power inverter that could handle 250 watts and then found a small electric heater at a local drug store that was marketed as the worlds smallest heater. It worked the one time I used it. That's not the optimal situation, but it worked in a pinch and was under $100.

[cashflyer]

Retrofit a webasto into the car. IIRC, that was the gas heater in Porsches.
http://www.webasto.us/am/en/am_auto_heaters.html

Or an espar. The link above has detailed info.
http://www.espar.com/

[Ringmaster]

Originally Posted by Flyin Brian

in Excellence a hot Rod 356 used an electric heater. Rally cars use them too. I don't know a brand, but a little research on rally prep shops may help. Looking forward to what u find out.

Really? Has anyone else seen small electric heaters for rally cars? Does anyone have a copy of this Excellence 356 article?

[RarlyL8]

The expense and effort to add this weight, complexity and cut holes in your car is more than fabricating a set of heat exchangers. Not to mention the maintenance.
Post a pic of the headers and I'm sure a more eloquent solution will come.

[DW SD]

I saw a solution where someone ducted air from the engine mounted oil cooler and routed to the longitudinal heater ducting. An inline marine fan may have bolstered the throughput rate.

Doug