Ep 368 Air Cooling Engines with Jake Raby

Air-cooling a Volkswagen engine has always been as much science as it is art. For decades, enthusiasts have debated which fan shroud cools the best, what compression ratio is ideal, which cylinder heads run the coolest, and how today's fuels affect engine temperatures. This week on **Let's Talk Dubs**, we're joined by one of the most respected names in air-cooled Volkswagen engine development—**Jake Raby**. Jake shares the incredible story behind the extensive cooling research that changed the way many enthusiasts think about building reliable, high-performance air-cooled engines. Beginning in 2006, Jake embarked on an ambitious cross-country journey in his famous blue "BluebonicPlague" Beetle, outfitted with more than 20 sensors strategically placed throughout the engine. Every mile of the trip generated an enormous amount of real-world data, with over two gigabytes of information recorded to analyze everything from cylinder head temperatures and oil temperatures to airflow characteristics and cooling efficiency under actual driving conditions. Rather than relying on opinions or bench racing, Jake set out to answer the questions that Volkswagen enthusiasts have argued about for generations—with data. In this episode, we take a look into: - The evolution of VW cooling system design. - The strengths and weaknesses of the various fan shrouds and cooling kits available today. - Why some cooling systems outperform others in real-world driving. - The relationship between engine displacement, compression ratio, ignition timing, and operating temperatures. - How cylinder head design dramatically affects engine longevity and cooling. - The impact of modern ethanol-blended fuels on air-cooled engines. - Common misconceptions about engine temperature and reliability. - The testing methods Jake developed to remove guesswork from engine building. Whether you're assembling a mild street engine, building a powerful Type 4, or simply trying to keep your classic Volkswagen running cooler and more reliably, this episode is packed with decades of hard-earned knowledge backed by real-world testing and engineering. If you've ever wondered what really keeps an air-cooled Volkswagen alive—and what actually works versus what has simply become accepted folklore—this is an episode you won't want to miss. DTM Shrouds 912 Engine Teardown link Jake's Road Trip data www.vwtrendsmagazine.com www.rosswulf.com use code LTD 10 To get 10% off yur purchase ICON Pistons Here