Here are some pics of my tornado xp's:

1. upgrade your 2 speed clutch bell to: http://www2.towerhobbies.com/cgi-bin...4&I=LXCLR2&P=K + http://www2.towerhobbies.com/cgi-bin...4&I=LXDHM0&P=K + http://www2.towerhobbies.com/cgi-bin...4&I=LXCLR9&P=K
you may need to widdle away a little of the upper plate post so the gears clear it

2. if you want more low end touque use this clutch bell: http://www2.towerhobbies.com/cgi-bin...4&I=LXM730&P=K you will loose top end speed with this but have much low end take off

3. upgrade your single speed clutch bell to: http://www.clermontmotorsports.com/s.../Detail?no=200 or this place: http://www2.towerhobbies.com/cgi-bin...?&I=LXLST9&P=7

4. upgrade to this clutch spring traxxas 4146x : http://www2.towerhobbies.com/cgi-bin...=++&search3=Go