[lincpimp]

Only thing sdp-si has in stainless mod1 with 5mm bore and set screw is 30t, then 36t. Not sure if a 30 will work for you. The tdr colleted adapter and Mikes hardened gears is about the only game in town over 25t... I have had good success with the 25t pinion and 63t spur. If you want more speed you can always go with taller tires! Losi also makes a tin coated 59t spur, but you may have issues getting close enough mesh with the tdr mount.