Gday to all, pretty new to the mower scene and currently building a Murray pan frame into an all terrain off road mower, it came with a 12 hp flat head briggs in it and I have a chance to purchase an 18hp opposed twin briggs also, thing is I have fitted a 12.5 oppy to it an physically it was too big to fit all what I intend down the track, alternator for one as the top pulley conversion will not fit under bonnet etc etc.
So my question is what would peoples opinions be on these two options, would you go to the trouble of fitting the opposed twin and maybe bonnet scoop etc to fit and more modding, or would I get a good performer out of building the 12 hp flat head, it needs rings at the least and a head gasket.
I really wanted a twin and not scared to mod either, but would I be gaining much or should I just build the single stronger, is weight gain an issue, I have a quad bike double a arm front end with suspension also fitted to it. Also would like to remove the gov down the track and play with it a little. any help is appreciated and taken into account, cheers to all.