UC Davis '16. Classic Cars. Old School JDM. Manchester United. Photography. I <3 my miata
Anonymous asked: What is anti lag? And why does it cause flames to shoot out?
It’s basically what you read.
anti: opposition of
lag: failure to happen in good timing
It’s a system made to keep the turbo spinning by igniting fuel and air before its location. That explains the pops you hear and the flames you see. Helping the turbo spin with an anti-lag system will help enable it to keep adequate boost pressure at any given time. The point where boost pressure isn’t really in effect when you want it, that’s lag and it’s no fun.
The “bang-bang” ALS systems that you speak of work by retarding the ignition timing off-throttle to the point that the cylinders push raw fuel out the exhaust laces and into the headers, THEN the spark hits and ignites the fuel in the headers. This causes a pretty violent spool of the turbine and spits flames out the tailpipe. It’s literally a controlled backfire.
It’s really hard on the exhaust valves (they’ll melt) and the turbo bearings (because of the stress o the explosion happening in the turbine housing).
Great for drag racing and other short runs, but the bang-bang has fallen out of favor in rallying because the engines have to last longer. Most rally engines now use a version of Audi’s old Umluft recirculating air anti-lag system.
Thanks for the input. Don’t want to spread misinformation.