I used a 2e clutch plate in one of my ke20 upright 4k fits straight in,in the supercharged 5k ive got a double diaphragmed pressure plate and trd clutch plate (theyre still available).I`ve run t50s behind my 1430 3k race starly but lap times are slower due to the weight penalty of the t50 in it being approx 11 kgs or so heavier,but in respect to a rally car its a more durable option and worthwhile if you want to go close ratio.Keep up the good work :P