Have you switched over to the symmetrical plug spacing heads or still running the ones pictured above ? I get the impression the symmetrical plug spacing heads were not good with the carbs but great with the FI.

AG.

1970 Challenger w/572 Hemi street car and my pride and joy. 1986 T-Type with 272 Stage 2 Buick V6 engine - True 8 second street car. Just updated the engine and put down 928 HP @ 35# boost to the ground on chasis dyno. 1976 Cee Bee Avenger Jet Boat - 460 Ford powered.