I've done this research before and I've spent the last 15 minutes trying unsuccessfullyly to refind the links.
But, I'm pretty sure that the record for an electric vehicle is 111.14mph. That's in Guiness and was set in Oct of 2004 if memory serves..
The record for a nitro vehicle is 109 point something but I could not find a link.
The record for a nitro boat is 125. something mph and I've seen reports of 140mph speeds for electric boats but, back when I first researched this I only found confirmed speeds in the low 120's.
The speed for a plane looks like 343.92km/h (213.7mph) set in 1971. I'd have thought it would be faster but that's all I could find.
http://records.fai.org/models/current.asp