If we're still talking about VW engines for the KR-1 - As I remember, Steve Bennett started out with a 1600cc on his original KR-1. He described the performance as "marginal". He eventually upgraded to an 1835cc, I believe, with about a 9.1:1 compression ratio (requiring 100LL) which gave him much better performance. I was privileged to fly it for about 50 hours or so and it flew very well and seemed to have plenty of power for me. I also had about 50 hours flying a different KR-1 with a 1700cc VW (simpler conversion from a 1600cc) which also seemed to have adequate power.
Ed Janssen
