I found my stock lights very good indeed on the super 8, if its second hand maybe the previous owner put cheaper or lower powered bulbs in? also make sure the alignment is correct as this will have an effect on how bright they "seem". i usually set it to aim just above a licence plate of a car about 2/3 meters away, this way u dont blind people but u light up whats in front pretty well.
I still have stock bulbs so cant help with the idea you have, sorry.