A long time ago Root werks and I were going back and forth in a thread about ways to make /6 headers produce cabin heat. He had tried welding some tubing to the bottom of the headers, IIRC, and said that it worked fine until you got some air over it while driving (heat tapered off). I had an idea of tubes on each pipe that would be interconnected and would possibly tripple the heat output, but today I was thinking about it some more and came up with a better idea. I think that it would be pretty easy to have some fins welded up on the exhaust tubes along the stretch that will be boxed in on each pipe. This would increase the surface area without having to increase number of heat tubes welded to the exhaust pipes. With this idea you should be able to get pretty good heat and it shouldnt be a whole lot of work. Just fin it, box it, plumb it (cost less than $2500 or more for the HE and you still get the header performance).

Ideas?

If you keep postulating you'll go blind...

Copper conducts heat really well, how about wrapping the exhaust pipe with

copper tubing, braze it in place. Then box it.Click to view attachment

I'd be interested in seeing something that worked as well. Been "thinkin'" about some solutions for a while myself.

Of course, why reinvent the wheel if someone has already done it . . .

Soft copper tubing is within my abilities (I have no welder) and you could coil it around the pipes. Maybe multiple tubes and then braise them into a common collector on each side. How to do it without it looking like complete crap, though? Interesting.

do what PMS does and simply box a section of the headers and blow air through ...

do NOT weld the box to the headers, just make two halves and pinch/press them together.

this will work fairly well ...
Andy

I had something similar on my old 3.2 conversion.

Ferg

update (found 2 lousy pics)

Ferg, were they sufficient?

Or do what I am thinking about. I'm doing a /6 conversion with headers and a front mounted oil cooler. I am thinking about building a heat exchanger/box heated by the hot oil before it goes to the cooler. Seems simple enough? Just need to figure out what to use for the heat exchanger?

I seem to remember them to be fine... But my cars do not often go out in bad weather I had no issues on cold mornings though.

Doc,
does this mean that your engine is back together and giving off more than black smoke. Sounds like you will be running at Hershey???

No....I am still awaiting a pin for my piston, but it is on its way. Sooon, sooo soooon.

Mike,

I've been debating the heat also
Once I had a email conversation with Roots Werk about it.

I recently picked up a set of the mid year 911 heat exchangers that face the wrong way in a 911... I'm sort of brain storming using them

my plan B, is to do the box thing with stainless (or even mild steel as a prototype) I picked up some shorty headers to play with.

love this thread
brant

I have the perfect headers for such an experiment, but I also have a cherry set of jet hot coated OE /6 exchangers It doesnt stop me from trying to solve our little problems.

Doc,

If you do make a set of the boxes for your headers, I'd be most appreciative if you shared your pattern and results.

I'm planning on using a set of the MSDS headers for my six conversion. Long way to go before I get there though.

Awesome, I am looking forward to seeing it run at Hershey

Encapsulating mild steel exhaust pipe for heat is not recommended, just as no welds (even on stainless) should be inside the heat collector.

"did you hear the one about the medical student that got carbon monoxide poisoning?"

The fabrication on Ferg's look functional enough, but if those are mild steel headers, I no likee.

BTW, the PMS exhausts are B & B. Between 50 and 25% of the B & B have fit problems. Next set I get/sell/try will be from GHL.

http://www.ghlmotorsports.com/Merchant2/me...gory_Code=PH-NT

So a great "lifetime" set of stainless headers with heat cost $1000 more than a set of modified headers. The extra money won't come in handy if you are dead.

The oil cooler heat seems like a good idea. I know a couple guys who are trying that approach, but I don't know how it's come out.

Ah Perry, you remind me of the reason we were thinking of using tubing (enclosed system) instead of what I was proposing in the 1st post. I guess that coiling tubing would be the only other cheap alternative.

the factory heat exchangers (914/914-6/911) are all steel covered with steel...

look in the current classifieds to see an original 914/6 pipe rusted away

Oil doesn't get hot enough. Your talking 300 to what over 600 deg.

Doc, I could build you a nice set of heater boxes that would be function nicely cheap. Way less that 2700.00 But you live too far away.

try these Looky

Coolant temps in water cooled engines are around 180 deg. so why wont this work?

I have had a pair of the B&B stainless Steel heater boxes on my 914 for almost 2 years now. They have good air flow, but don't really get all that hot which isn't needed in my area. So they work really well. They were $1800 back then. I remember the tube idea I did and is probably still on the flared orange six I did years ago. It worked REALLY well in town until you got on the freeway, then the tubes cooled down to almost cold air. But in town it was really nice and toaty warm. Wish I could have tried insulating the tubes.

that should work, but you'll need to plumb it a bit different so that you can suck in the warm air with the stock fresh air blower.

in the stock configuration, the fresh air blower never sucks in the hot air from the ducts in the longs.
in order to force air through the cooler (think stop & go traffic), you will have to modify your airbox to suck from the warm air inlets ...
Andy

just run a something like a tranny cooler on the scavenge side that would be mounted inside a box that the heater blower would blow thru then on to long duct.

yeah, but he was talking about a front mounted engine oil cooler. which is what i have. it gets plenty up front, but when you're in stop/go traffic, there's no forced air flow, thus you wouldn't get any warm air inside the cabin.

the fresh air blower is in the perfect place to be reused to blow the warm air from the front cooler into the cabin ...
Andy

Good discussion going on here

rick, I dont need a set of HEs. luckily, but thanks for the offer. I have a nice set of stockers for my /6 that were donated and salvaged through the net work here I am just thinking of ways to warm the cars because it is cold here and I am going to need to put some type of HE system on my future bus/vair conversion some day (oh no, here he goes again with the damn vair).

I like the cessna HE idea. I bet I cold make something similar for less.

The problem with Dan's set up with the pipes is that there is not enough surface area to get heat saturated and combat the airs cooling effect. In particular, with internal surface area that is not exposed to the cooling air flow, you would be able to keep the air warm.

Is it OK to weld stainless to stainless in the idea that I had with the fins?

As for the oil cooler concept, Rennegade already has a water cooled set up that employs many of the concepts you guys are talking about, but with water. I bet you could copy their blower set up and plumbing for the oil lines and put them in the same place as the heater core would have gone. You may even be able to utilize a smaller front cooler as the heater core, even when not in use, would provide extra surface area for shedding heat. I would even immagine that plumbing the oil cooling system would be easier as the lines would be smaller than the H2O stuff. Would you need an extra oil pump to flow through all of that plumbing and the cooler, though?

They're $100 bucks...

I think that's one of the best ideas I've seen presented here in a long time.

$400 GPR Headers
$250 Heat Boxes
$650 for a new system out the door?

No brainer.

That should work. It is such a short trip from the front of the car to the blower box

I doubt you would need to up grade the oil pump.

Ah, I ass-u-med that since they were aviation they were expensive.

I built some heater boxes some 30 years ago on a turbo 914. The Crown kit headers didn't have any, so I made my own which worked as well as the stock ones. Notice that the stock heater boxes on a -4 are pretty long, and the air flow runs down one side, makes a turn ,and returns to the front. Plenty of time/surface area to heat the air. I employed the same thinking when I built mine making sure the devious path idea was copied. I basically brazed some sheet metal boxes together.

Andys

Heat doesn't have to travel far in a small aircraft.

Anyone with vintage heat exchangers would probably be well served with this little CO1 dectector.

http://www.wicksaircraft.com/catalog/produ...2816/index.html

Remember that oil usually takes quite a while to come up to temp--longer than the coolant in a water-cooled car. And you usually want a thermostat to keep cold oil out of your cooler (for various reasons), which means that in cold weather you may not get heat for a looooooooong time...

--DD

That is a valid point but I'm in Orlando Florida where it get's into the 30's for maybe 1 week out of the year. I'm really looking to add some heat don't really need that much. If I'm running oil lines up front for a cooler anyway I think building a small heater box in the front trunk to go between the engine and the cooler would be relatively easy. Just in the concept stage.

I like the cessena HE idea. Get some basic headers and weld some heat sinks(fins) on them, wrap them in the aviation HE's and see how it works.

Mister Evil, you gonna give it a whirl?

Not any time soon, I just like to think out loud.

Chirp, Chirp, Chirp, Chirp, Chirp, Chirp, Chirp, Chirp, Chirp, Chirp, Chirp, Chirp, Chirp, Chirp, Chirp, Chirp, Chirp, Chirp...

these are awesome:
http://www.webastoshowroom.com/blueheat/index.html

gas heaters. they will cook you out of your car. I had on in a ghia vert.
the new ones are much more "safe" than the old 50-60's vw/porsche versions.

a little pricey at 1800 (installed) but if you want real heat in an aircooled car... this is the only way to go.

Nah, I want to salvage gas milage, $$$ and such. You can heat an air cooled without one of those. The heating systems just need to be maintained once they are functional.


Eric,