Hear ya are!!!! Go to FLETCHES CARBURATED 5.0. Data on all the stock heads back to 1968 including the Clevelands and aftermarkets plus a lot more. Note the Cleveland head airflow is not any better than todays good heads. Note how well the 69-70 DO heads do when ported compared to late E7 heads. We use the N351 on a track engine by rules and make over 500 hp with untouched castings, burning straight alky fuel. Book mark and enjoy.
what web site are you talking about? i can't seem to find anything for fletches carburated 5.0 or ford performance heads.