I remember seeing one of Dave Dudeks motors for sale a while back. These numbers might not be exact but I believe it said over 25K invested. The reason for the sale. A new bullit to remain on top. There are guys who can come up with 20k for a motor,once. Then after a season they're behind. I personally can't afford 20K on the whole car, much less a motor. Then you have to deal with the yearly rule changes. I raced NMCA and NSCA for many years, though not in the heads up classes. I made many friends who were racing heads up. It's a very expensive and VERY time consuming venture to stay on top. Personally I like the no electronics index racing that N/SS racing provides. No dial-in change over a few days,no trans brake. A guy asked me once how do you stay on the dial with weather and track changes. I told him I tune with a stick and a stone.
Doug