Cant bear in mind just what the B is, but TDC is Top rated DEAD CENTRE for for timing. All 20V's, whether for the coast or highveld should have a btdc of ten deg. Meaning your inventory timing must be established at 10. The engine's AFR looks typical at cruise, https://mylesroxtw.digiblogbox.com/59230022/not-known-facts-about-4age-20v-for-sale