Have just put a 5.7 litre V8 into an S10 Blazer which is pretty much the predicessor to the fronty. If I give it some welly 4th gear ( auto ) will drop in at 80, unfortuneately the clock only goes up to 85, havent set the tracking up yet ( front wheels point sort of in the same direction ) so I lost my bottle at about that point, oh and the 6mpg was at the back of my mind as well!