I have a nice shiny OBX Racing aluminium lightweight crank pulley that will fit a MK1 MX5. Bought for a 1.8 but believe it should also fit the 1.6
According to the blurb it will give an extra 5-7bhp.
Still in its box, never fitted. Cost me in excess of £80 from the states

Looking for £40 + postage

[Edited on 4/1/15 by Tazzzzman1]