Does the EH55 do any upconverting?

Yes up to 1080i (I believe) via it's HDMI output. It does progressive scan via component. I don't have the EH55 but I do have the EH75V which is basically the same unit with a VHS combo deck and smaller HDD.

Thanks vferrari.

I have the EH55 but I use the PDF manual as it's usually more convenient for searching. When searching the PDF for upconverting nothing comes up so I wasn't sure about it.

Check page 63 in the manual. It is under settings for the HDMI resolution, not under "upconversion" as a PDF search term.