You probably could. Bore enters are close and you would have to change cam sprockets to work with standard SOHC chains as DOHC had Hy-vo cam chain. No, wait...you could use DOHC crank and then do the Hy-Vo primary drive conversion. Oh, that sounds like a winner!
We run a couple of hy-vo motors and their the ducks guts. But I'd have to agree I can't see a lot of benefit fitting an 16v head to these motors.
I don't believe these motors produce anything worthwhile re; power over about 8'000rpm.
We've played around with big cams with a lot of overlap and all we where getting was a lot of noise at the expense of throttle responce, reliability and good usable power.
It may be a different story for the Drag blokes and I'm happy to stand corrected, there are certainly greater minds than mine contributing to this forum.
Oh, and now that I've worked out how to post reasonable quality pics, if anybody would like a particular pic of the internals of our motors, one's partially stripped on the bench and our regular race motor will hopfully be the recipient of a new camshaft courtesy of MRieck tomorrow or the day after depending on the USPS.
Cheers,
Brian