BT46B Fancar
Brabham designer Gordon Murray came up with this car to increase downforce. It had a horizontal fan at the rear and took its power from the main gearbox. The car avoided an initial ban by cunning claims that the fan's main purpose was for engine cooling. It only lasted one race, however: the Swedish Grand Prix of 1978, where it excelled on an oily surface as other cars slowed. Even at a standstill, it could be seen squatting as the engine revved. The Fancar won the race but the FIA banned such cars from F1 soon after.
Lotus 49B
After a season to forget for Lotus in 1966, when F1 increased the engine size to 3.0L, the team bounced back in 1967 with the Lotus 49. In 1968 the 49B introduced aerofoil wings, again in an attempt to increase downforce to allow for faster cornering. This spoiler was positioned high above the car and bolted directly to the suspension, but after several breakages that led to near-fatal accidents, F1 took the step to ban the high wings and Lotus was forced to mount future spoilers directly onto the bodywork of the car.
Active suspension
He gave us the 49B, but he wasn't done, as Lotus founder Colin Chapman also came up with computer management of hydraulic suspension in the early 1980s. As technology developed, F1 teams Lotus and Williams both picked up wins using active suspension. By 1992, Williams' system was so advanced that Nigel Mansell cruised to the championship. Teams realised it was essential, but the FIA had concerns about cornering speeds so put pressure on teams to accept a ban, which was implemented in 1994.
Turbocharging
Introduced to F1 by Renault in 1977, turbocharged engines were fast but Renault didn't finish a race that year and it was 1979 before Ferrari's Jody Scheckter won a championship in the 312T4. Turbocharged engines began to dominate and ended the Cosworth DFV era. But again, the FIA stepped in, saying the danger and expense of the engines were affecting the sport. The maximum boost of the engines was limited in 1987 before the Turbo Era, as it became known, came to an end with a ban in 1989.
Exhaust technology
The latest F1 ban, which almost came into force at this month's British Grand Prix, concerns using exhaust systems to increase downforce. Certain teams (Red Bull started it) have been tuning their engines to direct gases into the diffuser area, even when off throttle. This smoothes airflow, increasing both downforce and cornering speed. As a result, lap times are decreasing by up to a second. The proposed ban caused an uproar and teams were given a stay of execution until the end of the season.