Cant keep in mind just what the B is, but TDC is Best Lifeless CENTRE for for timing. All 20V's, whether on the Coastline or highveld must have a btdc of ten deg. Which means your inventory timing need to be set at ten. iirc the throttle opener is utilised https://jasperdcujx.ambien-blog.com/41096115/getting-my-4age-engine-for-sale-to-work