To MAKE it a 4 mil and run good you will need 4 mil crank, stroker pistons, stroker domes cut for your cool head (or stock head cut depending on ehat u have) then u will have to have a banshee builder (on here) port your cylinders to match the stroke. Thats the bare minimum. All other mids like bigger carbs, better reeds, more timing and compression, better pipes, will maks this setup run best. At minimum a good set of pipes to match it, u could run stock reeds and carbs with clamp on filters and u will be fine Sent from my LGMS210 using Tapatalk