How many points were awarded to the Ford DFZ 3.5 V8?
CREATE TABLE "complete_formula_one_results" (
  "year" real,
  "chassis" text,
  "engine_s" text,
  "tyres" text,
  "points" real
);
SELECT SUM("points") FROM "complete_formula_one_results" WHERE "engine_s"='ford dfz 3.5 v8';