A few years ago I bought a couple of 4 cylinder engines from another member in the Seattle area. One was a 28 which I kept but the other one was a 27. The story was that it was used to power a wrecker in a junk yard. The interesting thing was that they had used a distributor out of some Chevrolet V8. Probably a 283, or a 327 and they used every other distributor cap hole.. The vacuum advance was hooked up, no mechanical. I have another 28 engine someone rebuilt and it has a 4 cylinder Autolite distributor with the vacuum advance.