Luciano, I have seen the max forward voltage. I thought it meant on average.

Im using more LEDs now. Ive re-arranged the circuit a little so that theres hardly even room for the 2 screws and ive got 48 LEDs on it. Its a bit less cramped on the track side because each LED only has 2 legs instead of 6. There are 12 LEDs in each color. The datasheet says 4.2V max for the white ones. If i have groups of them in parrallel (4 LEDs in each group) and connect the groups in series then i should end up with 4V per LED. I think that means they would only use 150mA per color too