I am going 164 vented with 240 gt calipers which are 2mm bigger piston dia. The 164 pads are smaller than my 144 b20e which has same as 240 gt. Mounting holes need drilling but are same centres. Brake lines can be used by drilling and tapping [deepening]caliper for flexible hose and cutting and joining 140 and 240 steel pipes with sleeve and silver solder. Also fitting 145 rear limiters which have higher blowoff pressure to counteract for bigger pistons in front. I dont know how 240 disc on 140 hub lines up but do know that 240 hub and disc is miles off. My original brakes are excellent but like the idea of bigger pistons and vented discs as a good upgrade and mines bigger than yours oneupmanship. Good luck. Regards Jack McIntyre.