LDA screw allows you to tune the initial position of the boost pin. In order to see the full range of LDA enrichment, you want the follower pin resting on the largest diameter of the taper at zero boost without also contacting the step adjacent to the ramp.
...BTW your Bieber avatar is awesome.-Malone
I found this to be a good read:issuu.com/rswords/docs/bosch_ve_manual
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