I agree.. the cost of rebuilding vs new your better off with new.. I'm running W-2s which are iron and weight more(about 40# per set) but they can be made to flow well.. I have mine at about 312 cfm(might be 315 now)but they are about max now.. I have a set of W-5s but an having a issue with them at the present time.. but I will get them right.. they flow 319 at 600 lift.. both take off set rockers.. but the alum W-5s are 40#lighter