How does anti lag work?
28-08-2012, 07:12 PM
#2
Regular Contributor
Basically your trying to make enough gas in the exhaust to spool the turbo into boost so there is minimal lag when you set off.
Put it simply, the ECU turns the ignition timing about 45 degrees back, so it sparks with the exhaust valves slightly open, then the ECU squirts more fuel into the engine for a bigger bang, the engine fires with the exhaust valves open, causing the turbo to spool up.
Which is also why you get fuel igniting in the exhaust
Put it simply, the ECU turns the ignition timing about 45 degrees back, so it sparks with the exhaust valves slightly open, then the ECU squirts more fuel into the engine for a bigger bang, the engine fires with the exhaust valves open, causing the turbo to spool up.
Which is also why you get fuel igniting in the exhaust
Last edited by Cardie; 28-08-2012 at 07:14 PM.
28-08-2012, 07:13 PM
#3
Anti lag works on closed throttle situations, (aggressive ALS will run a trailing throttle ALS though)
It works by a valve bypassing air from one side of the throttle body to the other, allowing the engine to rev up as if the throttle was open. The ecu will then cut fuel and ignition in a sequence of which will allow the engine to run but also to ignite excess fuel whilst passing through the engine and ignited in the exhaust manifold. These explosions in the exhaust manifold cause the exhaust wheel of the turbo to be turned, each explosion will obviously work in turn and drive the exhaust wheel hard on each bang.
The more air bypass the more aggressive the ALS can be.
It works by a valve bypassing air from one side of the throttle body to the other, allowing the engine to rev up as if the throttle was open. The ecu will then cut fuel and ignition in a sequence of which will allow the engine to run but also to ignite excess fuel whilst passing through the engine and ignited in the exhaust manifold. These explosions in the exhaust manifold cause the exhaust wheel of the turbo to be turned, each explosion will obviously work in turn and drive the exhaust wheel hard on each bang.
The more air bypass the more aggressive the ALS can be.
Last edited by J1mbo; 28-08-2012 at 07:15 PM.
28-08-2012, 09:31 PM
#6
I've found that life I needed.. It's HERE!!
I've read about "EGR" ALS on this very site and to my understanding they just use an EGR valve to pump air directly into the exhaust manifold from the compressor housing of the turbo?
28-08-2012, 09:40 PM
#7
PassionFord Post Whore!!
Thread Starter
Thanks for the explanations. Jimbo, cheers for that. I thouht there was injetor in the exhaustthat injected air to burn any remining fuel in the system at first. But all understood. Cheers 
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29-08-2012, 04:51 AM
#10
Professional Waffler
29-08-2012, 04:53 AM
#11
Professional Waffler
you just use the egr valve to connect the compressor outlet to the turbine inlet, creating a turbine engine!
29-08-2012, 07:27 AM
#13
That's my understanding of it!
29-08-2012, 08:23 AM
#14
Professional Waffler
Nearly Correct it takes air from the inlet manifold side into an accumulator and when off throttle solenoids allow the air to be released through the egr valve and into two sides of e manifold, the fresh air reacts with heat and fuel and causes even more aggresive ALS
That's my understanding of it!
That's my understanding of it!
29-08-2012, 09:53 AM
#17
10K+ Poster!!
29-08-2012, 12:28 PM
#20
10K+ Poster!!
Don't know if this pic is any good
And this classic clip
And this classic clip
29-08-2012, 08:38 PM
#26
stage4 2wd cosworth
i want anti lag ant launch control on my saph also want more power... dunno what road to go down tho, either way it will be some shoppin list no doubt
30-08-2012, 11:11 AM
#36
Professional Waffler
30-08-2012, 11:22 AM
#38
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I've never tried my LC yet that's why I'm only asking to see if mine will do same as the above and spit flames..?... Someone on another thread said switch them both on but I don't want to if your not suppose to lol
Cheers Mat.
Cheers Mat.
30-08-2012, 02:27 PM
#39
Matt, if you turn them both one, only one will work at any given time.
LC is when you are stationary, as Gareth says with your foot on the gas and clutch, then when you drop the clutch and go, the next time you lift off the throttle to change gear or coast the ALS will operate to keep the turbo spinning.
so, with your LC do you have to engage it by pressing a button then put your foot on the gas, and release the button once you are moving?
and yes, LC will pop and bang and clatter when in use.
so will ALS LOL
LC is when you are stationary, as Gareth says with your foot on the gas and clutch, then when you drop the clutch and go, the next time you lift off the throttle to change gear or coast the ALS will operate to keep the turbo spinning.
so, with your LC do you have to engage it by pressing a button then put your foot on the gas, and release the button once you are moving?
and yes, LC will pop and bang and clatter when in use.
so will ALS LOL
30-08-2012, 02:54 PM
#40
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Matt, if you turn them both one, only one will work at any given time.
LC is when you are stationary, as Gareth says with your foot on the gas and clutch, then when you drop the clutch and go, the next time you lift off the throttle to change gear or coast the ALS will operate to keep the turbo spinning.
so, with your LC do you have to engage it by pressing a button then put your foot on the gas, and release the button once you are moving?
and yes, LC will pop and bang and clatter when in use.
so will ALS LOL
LC is when you are stationary, as Gareth says with your foot on the gas and clutch, then when you drop the clutch and go, the next time you lift off the throttle to change gear or coast the ALS will operate to keep the turbo spinning.
so, with your LC do you have to engage it by pressing a button then put your foot on the gas, and release the button once you are moving?
and yes, LC will pop and bang and clatter when in use.
so will ALS LOL
The LC on my car works off the handbrake as The button mate...I need to wire it up and try it... Hope it's like dougs....