Hello and engine questions

[harky]

Hi, just joined this site, from the UK but cant find anything nearer!
Anyway i have a 8x8 argocat, think its 1980s but not sure. It orgionally had a Tecumseh OH160 16hp engine but it gave problems so I replaced it with a Honda GX390 13hp. My feeling with this engine is that it is maybe slightly underpowered and makes the argo fairly slow. I've heard rumours of people using small car engines. I was thinking along the lines of an old mini cooper engine, 998cc and 48hp. Has anyone ever actually done this? And would my current transmisson take the extra hp?
Any help would be very much appreciated, Andrew

[AussieMax]

more grunt

If you plan on floating the thing at some time, a car engine would be far too heavy. The 13 hp honda isn't enough for an 8x8. The easiest thing to do, and probably the cheapest in the long run, would be to fit a larger honda/briggs/kohler/kawasaki stationary engine. That way the clutches etc would be easier to fit, the transmission should handle it and the weight would be minimal. You should be able to fit something around 25hp with little modification. That will get it moving a lot better.