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Evolution Two Cooling Fans for Doghouse and Early VW Fan Shrouds

If you have been following along, you know that my lightweight cooling fan has been out of stock for a long time, as I developed a "Next Generation" fan to replace it. In that development, at the last minute, just before release I had one explode in RPM testing. This caused me to not be able to release the fan as a product, and I couldn't produce the original anymore, because I had put all my capital into the development of the NG (Next Generation) replacement, and had no capital to even manufacture the original. In fact, I was quite a ways in the hole because I had purchased the production materials, and produced a very large number of NG fans in anticipation of those final tests having no issues. Well, that really put me in a bind. The good news was that my Evolution Two cooling system, with its dual inlet design passed the same high RPM testing without issues. So, that gave me a way forward, if I could find a way out of the financial hole I was in. From the fact that I'm still here, we have managed to get out of the hole and start producing and selling products, and I am able to take the design of the fan for the entire cooling system product, and scale it down to both the late VW ('71 and later) Doghouse fan shroud, and the early VW (pre-'71) fan shroud, and have them live at high RPM without issue! Well, I've done just that, and the results are incredible.

Again, if you were following the NG fan development you know that the increase in performance was nice, especially when coupled with a velocity ring. All the learning from the NG was incorporated in the Evolution Two cooling system with its innovative dual inlet fan. Scaling it down was relatively straight forward, but the proportion of the fans are unique to each fan shroud, based on the size of the inlet relative to the size of the new inlet that lives on the alternator/generator side of the fan shroud. So, each fan, the Evolution Two for the Evolution Two cooling system, the Evolution Two fan for Doghouse, and the Evolution Two fan for Early VW are all unique in their dimensions and proportion of how much fan is on each side of the fan shroud. With that explanation, let's talk numbers. First, the Early VW fan shroud results.

As you can see from above, the new Evolution Two fan for Early VW fan shrouds increases airflow by 25% when not using a velocity ring, and by 33.5% using a velocity ring. Or by 26.7% when comparing an OEM fan with a velocity ring to the Evolution Two fan for Early VW with a velocity ring. These are results that I'm very excited about, and hope you are too. Now, on to the Late VW Doghouse results!

Again, as you can see from above, the new Evolution Two fan for Late VW Doghouse fan shrouds increases airflow by 22% when not using a velocity ring, and by 28.5% using a velocity ring. Or by 23.27% when comparing an OEM fan with a velocity ring to the Evolution Two fan for Late VW Doghouse with a velocity ring. Again, I find these results very exciting! These products improve the cooling capability of your exising fan shrouds significantly over what I was able to do with the original lightweight cooling fan and the never released NG version of the lightweight cooling fan. As it turns out two fans are better than one. When you can draw air from both sides of the fan shroud, without modifying the fan shroud, it opens up an ability to truly create something ground breaking. You may have noticed that I'm not using the world "lightweight" in the name of these new fans, but they are lightweight too.

These Evolution Two fans for Early VW and the Evolution Two fan for Late VW weigh just 218 grams and 227 grams respectively, which is 81%+ lighter than OEM fans, which is also an incredible improvement of the original lightweight cooling fan, which was just 73% lighter than and OEM welded fan for the Doghouse fan shroud. So, even better throttle response, and even closer to my original goal. When I was in development of the original lightweight cooling fan, I wanted it to be 90% lighter than OEM, but could only achieve 73%. It was still very good, but I wanted more. I actually thought this new dual inlet approach wouldn't improve the weight savings much if at all, and was pleasantly surprised in the improvement, and it was also better than the NG version that I never released! So, what do you get with all this?

You get an inlet that serves as your backing plate, you get the fan and all the mounting hardware needed to put it together with your existing fan shroud, and it just bolts right in place, just like the OEM setup and your alternator or generator sits in the same place as before. If you couple this with my fixed cooling flaps, and a velocity ring (I'll have those available too), you have the ultimate cooling system upgrade (besides my Evolution Two cooling system), without much fuss at all!

Thanks to everyone that has supported me along this journey, and has been patiently awaiting the return of cooling system upgrades for existing fan shrouds. I really appreciate it, and look forward to delivering these products and future innovations to the Aircooled VW community!

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Jose P
Jose P
Dec 19, 2023

Is there a link to the videos?

Replying to

I have a lot of videos on my YouTube channel, so it depends on what video your referring too. Most of the same videos are on my business Facebook page too. Just search for Andrig's Aircooled Technology on YouTube or Facebook, and you'll find them.

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