Many thanks to Andy Holmes for sending these early 1500 engine images. Andy is the owner of an immaculate 1965 1500S Karmann-Ghia and is currently restoring an early '62 1500 Ghia. He's well on his way to having the bodywork completed -- check out Andy's restoration blog to see how things are coming along.
The first is factory press photo with another cutaway view of an early engine. It's interesting for its detail but also for the features it includes that didn't make it into production, such as the crankcase breather arrangement described here, the rubber strap that holds the top of the air cleaner in place (a metal clamp on production cars), a different tailpipe mounting arrangement, and the unusual plug wire separators that were used on VW's 36-horse engines circa 1960 (one visible just below the air cleaner). Andy's favorite feature: the artist's dramatic addition of a spark igniting the fuel mixture in cylinder #3 (upper left).
This is the engine bay of one of the 1500s on display at the Frankfurt Auto Show, the 1500's official public debut in September 1961. This photo provides answers to some questions I've had about when certain features were introduced. For one thing, it proves that the unusual features seen in the press photo above were all dropped sometime before full production began. It also confirms that the Knecht air cleaner should have a small washer under the wingnut. Air cleaners produced by Mann for the 1500 had a large, specially shaped washer that would have been hard to lose, but I've never seen a Knecht filter with a washer. Must've all gotten lost during service. The air cleaner doesn't have a connection port for a crankcase breather hose, so that supports the idea that the port was introduced around the beginning of 1962. Both of these images also show a full-sized Bosch coil. There's been some debate about whether the early engines came with a long or short coil, but these images seem to settle it. Interesting that there's no insulation under the engine trapdoor -- I wonder when that was added?
Thanks again, Andy. The obsessive engine detailers among us are much obliged.