Can someone share photos or explain how the hot air gets to the cabin from the engine? I have two curved pipes pointing downwards that come from the engine body (the curved tin area, not the actual engine). How does hot air move from there to the car? Thanks
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Top right - fresh air hose attaches either side of T1 engine cooling shroud to heat exchangers to tubes connecting to kit car battery (if provided),
Looking at Wolfgang's illustration, fresh air comes out of the engine fan shroud into the big pipe on the upper right. At the bottom of that image is a 3" diameter pipe that gozinto the right, or inlet end of that thing on the bottom, usually called a "heater box", that gets heat from the exhaust pipes. If you look closely, you can see how they go together.
At the other (left) end of the heater box is another 3" pipe outlet at the top. There is a piece of flexible aluminized pipe that connects the heater box to another 3" fitting as part of the car's frame. THAT's how heat gets into your car, but don't expect gobs of heat. A gentle warming effect is the norm.
Here's the heater pipe to use, fan shroud to heater box and heater box to chassis:
Brilliant, thanks. The kit-suppliers are supplying (not received it yet) an electric heater but not sure how that’ll work, especially demisting the windscreen. I’ll update this post when I receive the heater .
I wouldn't expect much! My CMC body has heater duct work under each door, the ducts in diagram can be connected (If you use heater boxes - OEM are best). There are threads here that show how to connect to the center tunnel for heat too. CMC has duct work under doors and stubs under dash for defrost. Photo is Not my CMC chassis but close - it looks like it used flex pipe to get air to front vs the steel sub-frame - mine has round stubs off uprights at front of doors. Note - a lot of heat is lost via those exposed steel pipes. Many add a boat bilge blower fan or the blower fans used in later VWs (and Porsche 914s). I would not pay any extra for an electric heater - use it for Fog-X coating.
Make sure your alternator can provide enough amperage to run the heater. They are real current hogs. I'm not sure anyone on this forum has had good luck with them. Bueller?
Um…
Never mind. You do you. Carry on.
@SteveMarson posted:Brilliant, thanks. The kit-suppliers are supplying (not received it yet) an electric heater but not sure how that’ll work, especially demisting the windscreen. I’ll update this post when I receive the heater .
We don't mention those here. That's like asking which oil is best, which builder is the best, when will SAS deliver a Speedster, what color Speedster is the best, will the PCA guys accept my plastic fantastic, and etc. All kidding aside the electric heaters draw A LOT of power and most alternators can't handle it and for those that can the output isn't worth the effort. There have been some previous posts on this, in fact there was just one recently that said quite a lot as to why the sizzle ain't worth the steak.
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Uh, Ok, heat.
First off, it would help to acknowledge that this is a car you will probably want to drive with the top down, especially after trying to drive it with the top up.
Next, that driving with the top down lets most of whatever heat you have escape out the top.
Third, that even the original cars didn't make much heat to start with and that our replicas don't try very hard to duplicate those systems.
All that said, decent copies of the VW heater boxes can make enough heat to 'take the chill off' on days that aren't super cold and even make enough heat to keep you warm if you admit defeat and put the top and side curtains in place.
My Kirk-era VS has a pretty simple set up that does about as good as you can do to heat the cabin if you invest in decent copies of the VW heater boxes. It looks like this:
The trick here is using 3" PVC pipe for most of the ducting. It's large enough diameter (and smoove inside) to get most of the air that's generated to where you want it going.
The rest of the, uh, 'ductwork' is flexible dryer hose, painted black (like the PVC pipe) to make it look like something that should be installed in a car.
As with much of the old VS hardware, notice that this is all readily available at very reasonable cost from Home Depot or from other local suppliers of quality home building materials.
However, if your expectations are still for heat and ventilation that rival modern vehicles, the most practical way for Speedster drivers to achieve that is to sell the car and replace it with a nice, used Boxster.
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If you’re serious about heat in a Speedster or Spyder, the only logical thing to do is a gas heater.
@dlearl476 posted:If you’re serious about heat in a Speedster or Spyder, the only logical thing to do is a gas heater.
Don't get me started........ 😉
And it is NOT the lack of heat produced by the engine that's important.
It's the 1,347 little air leaks in the cockpit that keeps it from getting warm.
As has been stated ad nauseum on this site, electric heaters aren't worth the effort. The math doesn't really work. The juice isn't worth the squeeze.
Gas heaters though? They actually do work.
TBH, all you’d need to do is install a cigarette lighter jack and buy some heated clothing to take your comfort zone down to the low 40’s. I used a Gerbing vest for years and they're fantastic. A jacket liner under a bomber jacket and a warm hat and gloves would be all you’d need inside a car.
An Espar heater is the cure.
^^THAT^^
Many moons ago I decided I wanted to take a shot at installing a forklift electric heater box in in a speedster, I purchased it from DC Thermal Inc . I figured I could make it work and this is what I learned. A 50 Amp 600-watt 10,200 BTU heater draw requires an expensive 100 plus AMP off road alternator, a separate CCA 18-wheeler 12v battery, HD cables, clamps and relays. Did it work? ....Yes . Was it costly ? $1,000 back then! ) I had to replace the standard 12v battery with a slim line type relocating that so there was room for the large and heavy truck battery up front. The heater unit was mounted on the passenger side foot kick panel and that took up quite a bit of room. so a passenger would have to keep their legs somewhat off toward the tunnel and bent to avoid getting cooked by the heater. But I did make it work and the alternator was able to charge both the batteries. So, I gave myself a Silver Star for that endeavor. It's just not cost effective nor is there room to do it right and that's why there are heater boxes or gas heaters.
Steve is in UK - so probably defrosting the windscreen is his main concern for needing some heat. I think with OEM heater boxes and a couple 12v blowers he could accomplish that. UK is not known for bright sunny days!
@WOLFGANG posted:Steve is in UK - so probably defrosting the windscreen is his main concern for needing some heat. I think with OEM heater boxes and a couple 12v blowers he could accomplish that. UK is not known for bright sunny days!
Has anyone tried the aftermarket in line air 12v blowers?
@Alan Merklin posted:Has anyone tried the aftermarket in line air 12v blowers?
Back in the ‘80’s I had a Ghia that the previous owner had installed small bilge blowers under the rear seat. They put out an amazing amount of heat. Obviously this only works if you are running heater boxes.
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@SteveMarson posted:....The kit-suppliers are supplying (not received it yet) an electric heater but not sure how that’ll work, especially demisting the windscreen. I’ll update this post when I receive the heater .
I wonder if the 'electric heater' that Steve is being sent isn't really just an inline fan (like the bilge blowers) to boost the amount of warmed air reaching the cockpit. His 'kit-suppliers' must know that making real heat electrically in these cars just doesn't work unless you use heavy, bulky, and expensive hardware (as explained by Alan, Danny, and others).
Taking a step back, considering the big picture and that Steve is in the UK, I'd again caution that these are essentially fair weather cars. You can use them in the cold and the wet, but you're in for an adventure if you try.
The heating system in my car (premium quality heater boxes and ducting as shown) lets me drive comfortably in 30-degree weather with the top (Br. hood) up. But rain or even heavy mist present other problems, caused by the lack of any properly engineered flow-through ventilation. The windscreen and side windows instantly fog over, severely enough that only towels will keep them clear. Combine this with seriously hampered ingress/egress with the top (Br. hood) up, and any semblance of practicality goes, well, out the side curtain.
I should add that I've replaced the standard side curtains with ones that don't quite meet the top, (OK hood). These are Troy's Cruzin' windows, that keep most of the warm air in, but allow enough ventilation to keep fogging to a minimum, as long as it's not actually raining.
But, maybe I'm not giving enough weight to the fact that Steve is British. After all, we know what that might mean...
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I have a gasoline heater. It’s not the do all/end all. It’s great at churning out freaky amounts of heat, but clearing the windshield in a September rain in the “low country of Savannah/Charleston”? Not so much.
I’ve driven in 10° weather - the heat is not the issue. The issue is the car (and its occupants) hate everything about it.
My take? If I ever do another build, I'll carry a rag and some Rain-X, and focus my efforts on sealing up as many air-leaks as possible.
A real HVAC system for this car seems like a full system for a motorcycle. I’m sure you could, but why?
@Alan Merklin posted:Has anyone tried the aftermarket in line air 12v blowers?
My first Beck had a bilge blower in the engine compartment as an auxiliary fan. Becks have a shelf in front of the engine over the transaxle that has plenty of space on it for one.
I have some small inline fans I plan to add to the hoses going to the defroster vents. I have already added a small dash switch for them. Unfortunately, they are somewhat noisy.
I have a gas heater. It takes in fresh air from outside, heats the heck out of it (I can push it to around 300F/150C) and blows it out just over our knees, but it is not a very forceful fan that blows the heat into the cabin (probably the crux of Stan's issues, along with air leaks). I do not have it piped into the Defrosters - I don't even HAVE defrosters! - But the windshield doesn't fog up, as it might if the heater recirculated cockpit air back into the cabin without fresh air in the mix.
I have driven comfortably (shirt sleeves, no coat) in cold down to around 30F/0C (top up, windows in), but have not done so in rainy weather - THAT would probably make a big difference.
I don't know where in the UK he lives, but winters in the midlands are about the same as here in New England (that's why they named it "New England", right?) so maybe electric heater(s) and some additional blowers in the ducting to get more airflow would be just enough for him.
And Stan is also right about the air leaks. Plug up most of them and whatever heater you have will get much more efficient. Every time I found and eliminated an air leak, it seemed like the heat got more even. "DUH!"
It ain't easy overcoming 1,347 different air leaks. 😉
Allow me to be frank. It's not the cold that is the problem - I can dress for the cold.
The problem is the car itself. Top down, motor purring, out on the open road - a Speedster is one of the most magical places on earth. I can drop into a groove and drive from sunup until way past midnight, and have.
Top up, a Speedster is one of the most miserable ways to travel imaginable - a tiny, noisy, cramped crypt you can't see out of. Visibility to the side, in the 3/4 rear-view, and behind is scary - I can't see anybody, and they can't see me. The noise (and I love noise and have the hearing aids to prove it) is like being inside a drum. Have problems with stress headaches? Top-up Speedster driving is not for you. I'm good for about 6 hrs before I'm really ready to be done. The problem is - nobody stops at the 6 hr mark.
I've got most of my air leaks stopped. I've got rollup windows, for crying out loud. I thought having real heat would make driving this thing with the top up tolerable.
I was wrong.
Forewarned is forearmed.
Wait a minute, you guys need heat in your cars?
Fixed it...moved to Florida.
Some really useful (and amusing) thoughts here, thanks guys! I had an MX5 a few years back and found it was a joy to drive with the top down on a moderately cold winter day with the heater on full blast. But as everyone says, it’s really a car for a sunny (or at least dry) day with the roof down. Will give this some more thought and do more research. Thanks again, guys, really appreciate the feedback.
Steve (south west UK)
