First off, back then Detroit was coping with new emission regs and mileage standards. The engines all had wimp cam shafts, low compression, small carburation and 2 something gearing. A lot of people blamed the Lean Burn system on the vehicles low performance. In reality, probably 75% of the LB system was dedicated to cold starts where the most pollution control was needed. But off it went and replaced by conventional electronic ignition. Cars didn't all of a sudden wake up and become capable performers from the switch. The LB systems in reality worked well but they had to be maintained. A lot of dealer mechanics were poorly trained on LB as well.