There's some serious work gone into that. He must have replaced the crown gear or something to get the gearing that high and I don't understand how he's got it to rev like that. Forced induction alone wouldn't do it, surely? Can't be a tractor engine. Also it appears to have front brakes and two wheel drive tractors of that vintage didn't. Can you do donuts without front brakes? Looks a hell of a lot of fun. That's the way to plough fields.
petrol i think. looks like a jetronic injection sytem of a merc or ford with turbo and intercooler. the only thing missing was the fury dice. love it.