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Old 23 July 2007 | 12:10 AM
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Default how does anti-lag work and.......

as above just seen a programme on ch4 about the greatest ever rally cars and of course the scoob was that man. it was showing the ins and outs of it and at one point mentioned the adjustable anti-lag and i wondered how it worked and is it fittable on a normal road going subaru.
anything would be helpfull as i find this very interesting.
also mentioned launch control?
Old 23 July 2007 | 12:47 AM
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stand alone engine management retards the ignition timing often with 20-40 degrees of delay, and the fuel/air ratio is increased as the driver lifts the throttle. With no spark during the power stroke, the exhaust valve opens while the spark is introduced and the unspent fuel and air travels down the manifold towards the turbo. When it reaches the hot turbo vanes it burns rapidly (bang) which keeps the turbo spinning. The response if full boost pressure at vastly lower RPM's. Most systems have user selectable maps for more or less agressive conditions and usually can be turned off for road use.

Anti lag will destroy a turbo but its not as bad as some make out... its a myth that you will only get a few hundred miles.
Old 23 July 2007 | 12:48 AM
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As far as I know, when you let of the throttle, it feeds fuel into the exhaust, before the turbo, this fuel ignites due to the heat, and this keeps the turbo spooling, this means that when you want the power, there will be no lag because the turbo will not have to spool up. the effect is that you get the flames from your exhaust, and the life of your turbo will be reduced, but that last bit is often debated!!

Scott.
Old 23 July 2007 | 12:50 AM
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well, mine was a little less technical, but I think I wasn't far off!

Scott.
Old 23 July 2007 | 01:23 AM
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i have anti lag on my ecu as well as launch control ! im tempted to get the anti lag wired in as i dont think it will harm my turbo as it a GT30R any standard turbo wont last long on anti lag. as for launch control its hold the clutch and rev!! once the rev's hit 5k it holds and if you dump the clutch its a 5k launch
Old 23 July 2007 | 01:36 AM
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Anti-lag is a waste of time as it doesn`t really do much apart from a bit of popping and banging, a flamer kit on your exhaust works just as well and gets the same sort of effect for a lot less money.
Old 23 July 2007 | 11:10 AM
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yessss, but youve forgotton the 'pub ammo'. A flamer kit is a bit crap when you can say 'anti-lag' or my personal favourite which is 'ALS' because then you can then have the smugness to explain the it means 'anti-lag system'.
Old 23 July 2007 | 11:16 AM
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which ECU's have it built into them or is it most aftermarket ones? it would be good to have it on a switch like the scooby WRC car.
Old 23 July 2007 | 11:42 AM
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Originally Posted by minty


which ECU's have it built into them or is it most aftermarket ones? it would be good to have it on a switch like the scooby WRC car.
some aftermarket ones
Old 23 July 2007 | 12:34 PM
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Originally Posted by Scooby-kid
As far as I know, when you let of the throttle, it feeds fuel into the exhaust, before the turbo, this fuel ignites due to the heat, and this keeps the turbo spooling, this means that when you want the power, there will be no lag because the turbo will not have to spool up. the effect is that you get the flames from your exhaust, and the life of your turbo will be reduced, but that last bit is often debated!!

Scott.
Correct, apart from it being a heavily retarded ignition that ignites the fuel, not the heat from the turbine vanes, as it needs a controlled spark to work properly.

It's also illegal for use in a road car
Old 23 July 2007 | 12:57 PM
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Why is it that Evos can get it added on as part of their ECUtek remap for £60 odd but its not an option for a scooby?
Old 23 July 2007 | 03:03 PM
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Originally Posted by Panthro
Why is it that Evos can get it added on as part of their ECUtek remap for £60 odd but its not an option for a scooby?
Think they're using opensource. And who says it isn't.
Old 23 July 2007 | 03:36 PM
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I have just had my Apexi replaced with a Simtek ECU and that has antilag. The exhaust becomes very hot after a few minutes use so it not really a road car thing. Mine is not as a aggressive as the rally car map they use but it's good for a laugh if nothing else and does make roundabouts more fun. It's not something I would use in a build up area as it's rather loud
Old 23 July 2007 | 03:41 PM
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jase @ scoobybits had it on his yellow type-r. that was supposedly a road going car, although me and him are debating this fact after he sold it to some nutter up in ayrshire

pops and bangs like a mother, and was really really loud. i question the "it knackers your turbo very quickly" line, as jase is well respected on here, and had it fitted no probs to his scoob for a while. i would say it depends on the size of the turbo obviously, as he was running something daft on it, so required anti lag. that or he hates old ladies crossing the road
Old 25 July 2007 | 06:31 PM
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Video of ALS - Photobucket - Video and Image Hosting

Old 25 July 2007 | 06:47 PM
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is that on your car gaz.
Old 25 July 2007 | 06:51 PM
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Originally Posted by hardsy555
is that on your car gaz.
Yep

Dunno which vid that one is, as PB is blocked at work, i've a couple of vids.
Old 26 July 2007 | 12:30 AM
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Originally Posted by GazTheHat
Think they're using opensource. And who says it isn't.
Can the ecutek software be used to map in a form of anti lag then? I'm having a remap done very soon and would be interested in finding more about this.

If it is possible, is it switchable.?
Old 26 July 2007 | 01:01 AM
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A bit of searching revels that the car can be mapped to produce pops and bangs like an ALS system but its not ALS. This can be adjusted to work within a certain rpm rage as well.

If you have a JDM car it can also be made switchable.!
Old 26 July 2007 | 01:23 AM
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Like i said above, anti lag is a waste of time on a road car and its basically just for pose value to let people know you have an uprated ECU. Anti lag will just blow your turbo eventually and its serves no purpose whatsoever on a road car when we have such low speed limits.

Its only value is for competion use where you need to keep the turbo spinning to stop the lag, get a flamer kit on your exhaust if you want people to see your flames and make a CD of an exhaust popping and banging to play in your stereo at full belt if you want to let people think you have ALS.
Old 26 July 2007 | 07:32 AM
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Pukka anti lag is very noisy and does age the turbo faster, and it all depends on how aggresive it is, you could call disabling the overrun fuel cut (with normal retarded ignition) 'anti-lag' as it will reduce lag, but the proper system on rally cars usually use idle control valves much bigger than stock (well now they run electronic throttles, but I'm talking 2002 ish) to get enough airflow, in fact the Escort cos WRC control valve had 3 times the airflow of a stock valve) and they didn't run richer than they would normally, you want combustion, not to run so rich it only burns at the tailpipe when theres extra air available!

Simon
Old 26 July 2007 | 09:49 AM
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Originally Posted by Borat_Drives_A_Scooby
Like i said above, anti lag is a waste of time on a road car and its basically just for pose value to let people know you have an uprated ECU. Anti lag will just blow your turbo eventually and its serves no purpose whatsoever on a road car when we have such low speed limits.

Its only value is for competion use where you need to keep the turbo spinning to stop the lag, get a flamer kit on your exhaust if you want people to see your flames and make a CD of an exhaust popping and banging to play in your stereo at full belt if you want to let people think you have ALS.
my god you're so boring.

Who needs a 300bhp 4x4 saloon when its a maximum limit of 70 and a mondeo would do the same job?
Old 26 July 2007 | 03:42 PM
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Originally Posted by rob2006
A bit of searching revels that the car can be mapped to produce pops and bangs like an ALS system but its not ALS. This can be adjusted to work within a certain rpm rage as well.

If you have a JDM car it can also be made switchable.!
That's right, but the rpm range is not true, it's on or off as i later found out.

That's all it is on my car, fake-ALS. So noises without blowing the turbo apart. You wouldn't know it's fake though, makes a right racket.

I keep promising to get it mapped back out, but i think the wifey has forgotten about it. TBH, the novelty is wearing off now, esp in-town driving.

When in the lanes though it still makes me you get the go, the looks, then the noise. Every rally nerds fantasy.
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