Sort of got back in, had a savage since they came out, first Had the 21.Anyways the bronco has ti shafts ,ti output axles,derlin gears lots of alum screws ,redseal teflon bearings,engine which is modded to rc car action specs.And a old pic from robin(thanks again, robin, radical cut man)it is a f 4.1 but with the header tank and the mods it is a crisp running mill at least .250% better all around going to be a good summer!