There is a fella here (wordslinger) that uses Leo Vince 4.5 gram rollers, Red Malossi clutch fly springs, and I believe the white Malossi torque spring. 50 mph top, and good take off. I am sure he will see your post, and give you all the info he has learned. You can also search his posts to read the whole process. That is a good scoot w/ the right mods. Just do yourself a favor, and don't try to "cheap out" on the parts. Buy the good stuff!