1. In order to combat the SPAM challenges we have been facing, I have chosen for the registration of new forum members to be manually approved. If you are registering as a new member, please fill out your profile as much as your comfortable doing. By doing this it shows us that you are not a spammer and will ensure that you’re registered to the form quickly. Should you be denied by mistake, please reapply with a fully completed profile
  2. I have received a lot of messages asking about the future of the forums once my car sells. Well today it sold and will soon be on its way to its new home. With that said, for the forums, there is more information under 'Announcements" titled "Future of the Forums' you could also copy and paste this link: http://www.trabantforums.com/threads/future-of-the-forums-donations.1762/
  1. turbofiat124

    turbofiat124 Premium Member Forum Donor

    So today I've been experimenting with boosting the air velocity on the heater. I'm sure I'm not the first person who has done this. There is all kinds of different fans people have rigged up on air cooled VWs.

    The actual heat coming from the floor vent/defroster is not that bad, it's the air velocity that "blows". The heater system is actually quite clever involving three heat sources.

    My main complaint is at idle there is very little air flow. It can take 10 minutes to defog the windshield in the morning. I've tried all kinds of those defogging wipes used on glasses. None of them seem to work.

    If I come to a stop, I can feel this sudden temperature drop in temperature on floor mode within the cabin.

    So I decided to mount this 4.0X10" blower fan in place of the elbow. I used the pieces below which involves a 3.25" to 4" straight transition coupler, a 3.25" to 4" 90 elbow and a 3.25" straight coupling. Not photoed is the 3" exhaust pipe. One end is 3" ID, the other end 3" OD so I used a short piece of piece of 3" silicone hose as a spacer to make up the difference at the firewall end. Using these silicone fittings reminds me of my turbocharging days!


    This is all this stuff mounted on the car. If this system proved successful, I was going to paint the blower and pipe black, remove the stickers, trim off the excess metal on the hose clamps and shave off the "feet" for a cleaner look.

    I had to delete the hose coming off the exhaust manifold going into the baffle. I was going to test to see which hose was "hotter", the one coming off the engine shroud or the exhaust manifold. But didn't get that far.


    This pipe had "Made in Canada" stamped on it but the sticker says "Made in Mexico"! HAH!


    So how did this setup work? The upside was the inside of the car did feel warmer. I was wearing my heavy coat at the time and could have removed it and still been quite warm riding around on a 40F cloudy day. Seems like without the blower, wearing a coat was a must.

    The downside was the heater is now noisy as hell! The fan itself is not the problem. It sounds like all the engine noise is being dumped into the cabin. I did not realize how well that baffle/elbow muffled the noise. My ears are still ringing!

    I also rigged up one of those outside temperature things with the probe mounted in the defroster vent. It was around 40F today and the heat coming from the defogger vent was around 135F on the highway doing 55 mph. I noticed at idle after making a hard run, the temperature rose to around 145F.

    Seems like with the hose that feeds into the heat exchanger from the engine shroud removed, there was a 15F difference in temperature. Deleting the hose did not make any difference in noise. So it seems all the noise generated is coming from within side the heat exchanger.

    So my next attempt was to mount a 3" fan after the baffle. I actually tried this fan once before but removed it. It didn't seem like it helped much with the car moving. But this time I could actually tell a difference in how much air it moved at idle.


    Now here is the deal. The 4" blower fan should fit in place of the short hose. All I need is another 3.25" to 4" transition coupling.

    The thing is, would using a larger fan make any difference in air flow? Because I'd still have to go back to a 3.25" inlet going into the diverter. So I don't know if that would act as a restrictor or not.

    One other thing I noticed is, when the baffle is firmly seated on the heat exchanger, the short hose does not quite line up. So the baffle/elbow has to be adjusted at the heat exchanger. I would imagine if it's not firmly seated and the clamp is not tight, some air leakage could occur.

    I have had the exhaust system off this car so I don't know if it's possible that I got the heat exchanger out of alignment when I reconnected it to the exhaust manifold or not (if that's even possible).
  2. kev the builder

    kev the builder Loyal Comrade

    it looks like it belongs there nice and neat, i would have thought it would have been a lot better at tickover/lower speeds, is the noise back to normal levels?i did notice on my car the heat exchanger can be moved a little as it hangs on the rubber bobbin mounting which will go soft with age/heat maybe a slightly different size one will help with the alignment,let us know how you get on it definitly looks like a winner
  3. Austinpowers

    Austinpowers Loyal Comrade

    You can get a kit from Demontweeks here in the UK that is like the last setup you tried. It is a universal kit for race cars, I have often thought about fitting it as I no longer have the pipe that goes from the motor to the exhaust manifold. Because I have the Mikuni carburetor you can't use it, unless you buy the modified manifold. I thought I could modify my old one but it's proved harder than I thought. So I think I will have to have a proper look at the kit.
  4. mbeamish

    mbeamish Loyal Comrade

    Anyone use their trabant DDR petrol heater . It looks sooooo dangerous bolted next to the fuel tank. I used to use my barkas petrol heater it was much larger and put out a toasty 3kw . However it was safely tucked in a separate compartment
  5. turbofiat124

    turbofiat124 Premium Member Forum Donor

    The engine noise entering the cabin is now gone with the baffle in place but the noise from the blower fan is still there. Not too bad but would be nice it I couldn't here it.

    One other thought was to go back to my original design using the 4" blower and use an actual muffler after the elbow in place of the straight pipe or hose. Here is one I found on Ebay that is 12" long that would probably fit. I'd just need to cut down another piece of hose to act as a spacer.


    The other idea was to build a baffle myself using wire mesh and fiberglass or something.
  6. turbofiat124

    turbofiat124 Premium Member Forum Donor

    What is it that Demon Tweeks sells? The intended application of the blower fan I used was a brake cooler. It's made by Atwood.

    [​IMG] [​IMG]
  7. turbofiat124

    turbofiat124 Premium Member Forum Donor

    Yet another consideration was to use an actual 6V blower fan from a Scirocco system instead of these tube blowers. I don't know if they are any quieter or not.
  8. mbeamish

    mbeamish Loyal Comrade

    Be careful Turbofiat I fitted a plastic blower fan in same position as you . It worked very well but after a couple of long runs it got so hot the plastic distorted and the fan jammed . I would seriously carry a small extinguisher with you while you are experimenting
  9. aardvark64

    aardvark64 Puttering Along

    These things often get touted as a poor man's supercharger. Seriously!

    Forced induction on the Trabi's air intake: the extra 2 bar of pressure must be worth an extra 20 bhp at the wheels...

    Neat idea, by the way. The heater, I mean.
  10. turbofiat124

    turbofiat124 Premium Member Forum Donor

    I do have the same concerns that the plastic housing might melt. Another idea is to mount the fan to the cold air duct on back of the grill and force it into the heat exchanger.

    This will be my next experiment if I have enough room for all this.

    The only problem is I might actually loose some heat. When I disconnected the metal hose off the exhaust manifold to see if this reduced the noise, it seemed like there was a 15F (8C?) drop in cabin temperature. But it was kind of hard to say for sure.

    Here is a 4" booster fan used on cloth dryer vents rated for 130C/266F. Only problem is the motor is 110V AC!

  11. Austinpowers

    Austinpowers Loyal Comrade

    Revotec Alloy In-Line Blower Fan Is one option that Demon tweeks sells. The other is the same plastic one as pictured above for cooling brakes.
  12. Ian

    Ian Loyal Comrade

    There WERE a couple of the genuine Scirocco heaters for Trabants, etc....ON EBAY RECENTLY??!!...
    One was a 6v and the other a 12 v type.
    Expensive relatively,..but were said to be complete.
    Search "worldwide" facility and you might still find one?....

    Interesting project and feedback though....keep up the good work!
  13. turbofiat124

    turbofiat124 Premium Member Forum Donor

    Well I have a couple of ideas.

    One is to mount this 4" fan on top of the heat exchanger (like I had it) but blow air into it the large hole and out the smaller hole, rather than using the fan to pull hot air out it. Maybe mount a small air cleaner on top of it for looks or connect some flex pipe to the cold air port behind the grill. That way it shouldn't melt the fan. Also this is more of a countercurrent flow so it might actually blow hotter air.

    I still have to come up with some solution to muffle the noise. One thought was to use one of those foam lined hoses like on my 2CV that is designed to muffle engine noise. It's the same ID as the short and long hose used on Trabants.

    I didn't think to pull one off my 2CV to see if this reduced the noise on my first attempt.

    Another idea might be to use an exhaust resonator. Here is one I found on Ebay for about $30 with the same size inlet and outlet as the small port on the heat exchanger.


    The other idea is to mount the 4" fan in place of the air cleaner sitting on top of the engine and blow air into the small port on the heat exchanger. That would probably be the easier and wouldn't require coming up with some solution to muffle the noise.

    Two problems with both of these ideas. I'm using a 4" fan to blow but at some point the inlet (or outlet) is going to be 2.25". So I don't know if this is going to restrict air flow and defeat the purpose. I thought about opening up the smaller hole on the heat exchanger to 3.25" which is the same size as the hot and cold ports on the diverter valve at the firewall but the starter motor won't allow it.

    Also I'm wondering if the baffle restricts the airflow. It's not collapsed or anything.
  14. turbofiat124

    turbofiat124 Premium Member Forum Donor

    So I did some more "experimenting" on my heater blower system today. I dug into my stash of leftover turbo parts for some exhaust pipes and silicone fittings to see what I could rig up temporarily.

    I mounted the fan to where it would blow into the heat exchanger through the big hole and out the smaller hole.


    The 3" silver ducting is for a clothes dryer exhaust which is weird since all I've ever seen is 4" ducting on American clothes dryers.

    It pulls fresh air in through the cold air duct to the blower. Then I used 2" flexible hose to go to the diverter at the firewall.

    This worked to some extent but there was still quite a bit of noise without a "muffler". It also looks like crap but it was just a test.

    Best I can tell the blower works better at pulling air through the small hole and out the 3.25" hose rather than the other way. I guess like an electric fuel pump which works better at pulling than pushing.


    So I robbed one of the heater hoses from my 2CV which has a foam liner to muffle engine noise to see what effect this would have:




    This did not go well. Just like the mediocre airflow on my 2CV, the foam liner which also muffles the engine noise on that car reduces down to 2" ID. This seemed to restrict the airflow even more!

    So I went back to the original IFA setup. This time I adjusted the baffle/elbow so that it's perfectly seated on the heat exchanger. For some odd reason, the short hose would not line up unless the muffler was sitting cockeyed. I used that same mylar ducting hose because the hose will no longer line up.

    I'm not sure what the deal is. I think the heat exchanger can only bolt to the exhaust manifold one way.



    I'm wondering if some air flow was escaping. I did not drive the car but did start it up and seems like the air flow is a bit better than before.

    So the conclusion:

    The 4" blower does in fact blows more air than the engine fan. It works best in place of the muffler/elbow but the noise is so horrendous, it's unbearable. Also like mbeamish points out there is the risk of the fan melting.

    Mounting the 3" blower after the muffler in the short hose doesn't do much if anything.

    I still have not given up on mounting it on top of the engine and forcing air into the small port on the heat exchanger to see what effect this has. I'd really like to find one of those fans from a scirocco system and push air through the small port on the heat exchanger to see if this particular fan pushes more air than the 4" blower I've been using.

    One thing is for sure. The engineers at VEB/Sachsenring put allot of work in controlling the noise exiting the heat exchanger. That's why that thing is so large (4" inside) which helps muffle the engine noise without reducing the airflow. The only thing they did not do is figure out how to push more air through it using an electric can. But the car was intended to be simple.

    That's all for now. If mounting the fan on top of the engine does nothing, this I guess this was all for naught...
  15. kev the builder

    kev the builder Loyal Comrade

    i guess what your saying is if you want more heat/airflow just go faster!youve been thorough and tried all permetations and the designers seem to have got the best solution
  16. turbofiat124

    turbofiat124 Premium Member Forum Donor

    Yes, if you can maintain a speed of at least 40 mph the cabin will stay "somewhat" warm in freezing weather on a cloudy with a jacket and ushanka! Just keep moving and don't come to a stop! It's a shame that the heat coming from the vents seems to be 100F hotter than the ambient air temperature but the air flow needs to be better to move it.

    However maybe the fan I am using does not generate enough CFMs and blowing through the small hole in the heat exchanger is the key.

    I have no idea how many CFMs the current 4" blower I'm using puts out. I found this blower which generates 270 CFMs which might work better:


    The only thing is it pulls 6 amps. I'm not sure if there is any juice left from my 6 to 12 volt converter. It power wire going to it is 10 amps.

    I might have to add another step up converter just for the fan.


    I'm not concerned about the amp output from the alternator. But I don't want to build a Rube Goldberg contraption.
    Last edited: Jan 5, 2017
  17. kev the builder

    kev the builder Loyal Comrade

    The lack of low speed heat isn't a big problem for me as it's not that cold here and I just tell myself it's still warmer than on my motor bike
  18. turbofiat124

    turbofiat124 Premium Member Forum Donor

    I don't usually get the car out much this time of year. It usually rains every day and hate to get it out in this nasty weather. When it's cold enough to snow, it's usually sunny and dry so that's when I tend to drive it in the winter. Like I've mentioned before, if the sun is shining, there is more heat coming through the windows than from the heater vent!

    I still wonder if there is some way to improve on the heating system without using an electric blower.

    Another idea might be to drill and mount a 3.25" hole and mount a snout on the side of the engine shroud (opposite the fan) and feed heated air into the cold air duct at the diverter and have both vents open. I think the ungodly noise I am hearing without the muffler in place is coming from the heat exchanger and not the engine.

    I would first make a copy of this panel out of fiberglass so if it didn't work, I can always resort back to original.

    That's my next plan. When I get something on my mind, it's hard for me to give up!
    Last edited: Jan 6, 2017
  19. turbofiat124

    turbofiat124 Premium Member Forum Donor

    I've heard that the 601 has an "improved" heater design. So I looked up to see what the P50's heater looks like. Well, It looks exactly what I was thinking about doing! Except I was going to mount a 3.25" snout and feed this into the cold air vent at the diverter valve.

  20. draku

    draku Newbie

    for more heat, close the rear engine metal casing bottom part
    this will increase air flow and heat
    also make sure that the small rubber hose between back of the engine blower and the exaust manifold is in right place
    you can try to insulate the exhaust muffler for more heat, but this can cause alot of rust

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