For sale is a Kent Cams Vernier pulley
I had this custom made by kent cams , and used this to fine tune my car to get the best spread of power.
I dont think Kent cams make these off the shelf and It cost me roughly £130. This worked wonders on my car and gained me roughly 7-10 hp top end by swinging the wheel.
This is an authentic lightweight Alloy type pulley and not a machined down mild steel standard pulley
Unfortunately the thread on 1 nut is rounded ,3 torque up tight. I used this fine like this since I owned my G40. but if you're a prefectionist you could dab some weld on the back and or tap the thread.
£50+ £5 P&P
Paypal accepted
(http://farm4.static.flickr.com/3486/3879158974_98efd50bb4.jpg)