the further the carb is away from the intake the more torque you develop. a down-draft intake would aid in faster delivery. but that would most likely require a fuel pump. removing a bend or two would help. hmmm, (5 mins later) are you running the stock muffler? preheated fuel is good for economy, but cool fuel is for power. if you do succeed in re-plumbing the carb away from the exhaust, you may need to adjust your mix to leaner if possible. i am unaware of any bolt-on performance enhancers, from what i see though, bigger engines usually benefit from smaller engines parts, ford, chevy, dodge, honda etc.. if you know your specs and find a rod or piston with a bit longer reach you will increase compression, same as decking a head. though decking will keep stock revs, stroking will take longer (to rev) and add torque. may require larger jets and or carb for stroking. longer pushrods, the list goes on.