Reducing Windnoise / Raingutter Fillers

VW beetle A pillar deflector

I’ve made several trips now with my Alfa Romeo powered 1303 Beetle. Most of these were on the dutch highways on which I drive around 120 km/h.
Now it drives really well on these speeds, but one thing annoys me. The sound of the engine is not the loudest sound anymore, now that I’ve gone water cooled. The wind noise is very loud! And it felt like the wind noise is mainly coming from around the windshield area.

I was wondering, could things be improved in this area?
I understand I can’t change the basic design of my beetle, so it will never be as quiet as a modern car. But would smaller modifications make any difference?

I asked this question at the forum, and Ricola (well known from his site told me about raingutter fillers that are used on Porsche 911’s. These raingutter fillers are plastic pieces that can be glued in the raingutters on either side of the windshield. It is said that these things will give you around 5 km/h more top speed because of increased aerodynamics. But they also reduce wind-noise. At least, that’s what the Porsche owners say in this Pelican Forum Thread (ignore the off-topic discussion..). There I also found this excellent airflow drawing:

Porsche 911 airflow drawing


The 911 has the same raingutter filler construction as the Volkswagen beetle, so it might be applicable for beetles too.

Raingutter Fillers

These are examples of raingutter fillers on the 911:

(click on them for a bigger version)

And here are the fillers before installing:

On the next page, I’ll be testing this idea.


    • Hi Jürgen,

      I have sold a few sets, but not much. They are still a bit “experimental”, I create them out of thin plastic using my homemade vacuum former.
      They require work to get smooth too, it is not a nicely finished ready to use product.
      I don’t have any sets “in stock” currently. I sometimes create them when more people ask about it, and then I create a few sets in a batch.


      • Hi Gerrelt,
        my request is nearly 1 year ago. I am still interested (as Jeff Kritz :))
        How long is your mail list of interested guys?
        We are just in front of a new Season……
        All the best for 2017

        • Hi Jürgen,

          I see what I can do… 🙂
          I hope I will produce some this year, preferabele before the season starts of course..

          Best wishes for 2017 to you too!


      • I have been trying for the longest to purchase a rear roof spoiler and a pair of reflectors from you without success. I’m reaching out again.

    • Hi Jeff,

      I can add your e-mail to a list, then I will inform you when I make new ones (but that take quite some time..).
      A set will cost around 30 euros.


    • Hi Khalid,

      OK, I will add you to the list.
      Yes, they will allow water to pass underneath. They are hollow, and there is a hole at the top and the bottom.


  1. I would also be interested in a set of these. I already have one of your rear window spoilers. Thanks.

    • Hi Rick,

      I will add you to the list (and make a mental note to start making a batch again…).


  2. Hej Gerrelt,
    here is one more to put on your list for gutter fillers. After traveling Germany north to south and back in my VW 1303 Bubster, I feel that I am in need for some aerodynamic upgrades. Wind noise is quite bad when cruising at 160-180km/h.

    Greetings from Sweden,

    • Hi Olaf,

      I just spent an hour or so going through the excellent build thread of your Boxer Beetle. Wat a brilliant build, very nice!
      Very cool car.

      I will add you to the list, and try to make some time soon to make a batch….


  3. I’d be interested ina pair of these gutter fillers and a rear window spoiler also. Can you get in touch if you have any for sale currently?

    • Hi James,

      I am currently producing a new batch, but they will probably all be spoken for.
      Shall I put you on the list?


      • Hi, yes that would be good, but it also depends on the price including the roof spoiler.
        Maybe you could email me?

  4. Gerrelt, very cool stuff you are doing.
    I am interested in the rain gutters and rear window spoiler for ’74 Super.
    – Craig

  5. Hi Gerrelt
    I’m also interested in a set of rain gutters and a roof spoiler. Do you still sell them?

    Best regards from Germany

  6. Hi Gerrelt,
    i`ve bought a Pair ofGutters a couple of years ago from you,
    i want to install them now,
    i remember that you send me an installation guide.
    Do me favour pls, and send me the installation again.

    Thx Harry

  7. Greetings Gerrelt,
    If the rear spoiler and rain gutter pieces are still available, I’d like to get in line to purchase them? Thank you, Ed

  8. Hi Gerrelt
    Are there any chance that you have a wind deflector set and a roof spoiler i stock, or planning a new batch?

  9. Gerrelt,
    I too am interested in a rear window spoiler and a pair for the rain gutters.
    I’m in Massachusetts, USA postal zip code 02738.
    If you are still producing these items, please send me a cost with shipping please.
    Thanks for sharing your mods.

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