I know John was trying to keep the power down on purpose and the atmospheric intake did its part. Since the VW barrel and piston was about 300-400cc at its stock stroke, he cut the connecting rod in half and joined it with the Honda 125 two-stroke roller bearing crank after cutting that connecting rod as well. He joined the two rods together with the resulting diplacement at around 250cc. The carb is tiny as it came off a 50cc two stroke engine. He figures it's going to produce about 2.5 horspower. I've included a somewhat blurry picture of the other, non-modified, half of a VW head. The other half is what he trimmed off lots of fins and such.
I watched him experiment with using just one ring versus two rings on the piston, since one didn't produce enough compression for him. He also switched out the atmospheric intake valve spring with a lighter one so it might idle better. Just amazing!
If he could make us engines to replace the outgoing HT's, that would be truly amazing! You don't see many people like this though. Most of the guys who work on engines that I have encountered replace them rather than build them themselves.
How much power does he think it could make without being limited?