There are two ways to go about this. An aftermarket anti-lag system like those that come with aftermarket ECUs like MoTeC and Simtek will adjust ignition timing during closed throttle situations to a point where the exhaust stream becomes really rich with unburnt gas. This is done by retarding the timing to about 40 degrees after top dead center. Top dead center is the point where the piston is furthest from the crankshaft. Rally cars use a different way of introducing gas into the exhaust manifold. There are separate injectors that introduce fuel directly into the exhaust manifold. Some of this mixture will continue burning in the turbine and down the exhaust system, resulting in the flames and explosions you hear coming out of the exhaust muffler. The use of anti-lag greatly reduces the life of a turbocharger and engine because of the extreme heat from the combustion in the exhaust manifolds. This is why it is normally only used in races and rallies and not designed for normal road use.
Watching , Waiting, passing time.
Last edited by archimedes00; 05-04-2008 at 10:32 PM.