Cant don't forget just what the B is, but TDC is Leading Useless CENTRE for for timing. All 20V's, regardless of whether for the Coastline or highveld should have a btdc of ten deg. Which means your inventory timing should be established at ten. i'm right here in cape city, https://holdenwuexs.blogstival.com/56387482/the-best-side-of-4a-ge-engine-for-sale