A lot of questions get asked about the boost pin, I thought I'd add a basic guide and a piccy for those interested in grinding their pins
The GTD boost pin looks like the picture below,
The extra fuel is metered by a pin in the pump that rides on the tapered section (note the wear mark from a standard GTD application)
As boost rises the pin is pushed down against a spring, the pin moves up the taper and more fuel is delivered
The more material is removed from the boost pin the more fuel is delivered
Also note that one edge has more taper than the other - by rotating the boost pin you can change the amount of extra fuel delivered. As standard this pin was fitted in the middle of it's range (evident by wear mark)
Note that more boost will push the pin further, up until approx 12psi when it bottoms out.
(note this is aimed at the newbie soot heads and is no way meant to be fully comprehensive)
I used a dremel and a grinding barrel(small) followed by a buffing rubber can then the cloth to get it super smooth.With a barrel type grinding stone it will be hard to grind more then one profile.I locked the pin in a vise and came down on it with the bearrel at an angle