At one time or another back in the early 70's, I owned and flew most of those older Enya engines. The first version you have was not a powerhouse by any means but was dead on reliable. If you ever choose to use it, be sure the old Perry carb has good "O" rings on the metering disc as an internal leak will leave you dead. I can't believe the carb would be in good condition after all these years. Later versions of the Enya 60, the II, III and there may have been a IV all gained power with each upgrade. If I was going to fly the Zlin with an old Enya, I think I would look for a stock 60 III as they were truly excellent in their time. Sadly I saw a number of those old Zlins crash back in the day and they didn't enjoy a great reputation. I never flew one so I have no idea what the problem may have been. A number of Maxey's designs were known to be snap happy as his choice of airfoils was not always the best. That was fairly common in that time period. He was a good builder though! I'm proud to say he taught me a few things about flying back in the day. He was a fine, proud, stubborn southerner (though transplanted to Iowa) that nobody ever won an argument or discussion with. Though he wasn't a close friend, I'm better off having known him.

Good luck with the Zlin and I look forward to a flight report.