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Hey guys,

Having a conversation today about anti lag setups with a mate. Now from my basic understanding, anit lag set ups for launch control work on the principle of a rich mixture combined with retarded ignition timing with your right foot planted to bring the turbo up on boost.

Now this is just a theory only, so anybody with greater knowledge can pick the holes in it but take the RB25 engine with its stock ecu for example and its "rich and retard" strategy when the afm volts get close to 5.0v.

The electrical wizards would know how to implement this but lets say you could make the afm see 4.5-5.0 volts with a switch or button hence putting the ecu in its rich and retard mode, you could then press this button, plant right foot and see a few pounds of boost pressure while stationary.

Obviously, it would depend on how rich and retarded the ecu made things and how much is required for anti lag but couldnt this work?

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I've only ever heard of mechanical antilag systems where the turbo is actually driven mechanically like a supercharger to get it spinning decently before you sink your foot into the accelerator pedal.

What you are saying certainly sounds interesting though

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I've only ever heard of mechanical antilag systems where the turbo is actually driven mechanically like a supercharger to get it spinning decently before you sink your foot into the accelerator pedal.

... and where did you hear that?

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"if u wanna completely shorten the life span of your turbo and your engine by dropping timing and dumping fuel into your engine to make the bang bigger........ go for it i'll help you pick up the pieces."

Thanks for that champ. I am well aware of the detrimental effects on manifolds, turbines and exhaust valves when used constantly but thats not what I asked.

Thanks for your input anyway.

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Hey guys,

              Having a conversation today about anti lag setups with a mate. Now from my basic understanding, anit lag set ups for launch control work on the principle of a rich mixture combined with retarded ignition timing with your right foot planted to bring the turbo up on boost.

Now this is just a theory only, so anybody with greater knowledge can pick the holes in it but take the RB25 engine with its stock ecu for example and its "rich and retard" strategy when the afm volts get close to 5.0v.

The electrical wizards would know how to implement this but lets say you could make the afm see 4.5-5.0 volts with a switch or button hence putting the ecu in its rich and retard mode, you could then press this button, plant right foot and see a few pounds of boost pressure while stationary.

Obviously, it would depend on how rich and retarded the ecu made things and how much is required for anti lag but couldnt this work?

Very creative thinking, what were you drinking?

In R&R protection, the rich is ~10% and the retard ~5 degrees. For any decent anti lag you would need ~30% rich and ~25 degrees retard. That way you would have sufficient unburnt fuel and the exhaust valve would be open when the plug fires.

Launch Control and Anti Lag are 2 different things. Launch control is for limiting the wheelspin.

;)

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While on this topic, does anyone actually run antilag on their skylines? Im seeing alot of WRX owners putting in Link ECU's with rotational idle/antilag setups and having very good reliability with them (granted, careful monitoring of the compulsary EGT gauge is required) with next to no mechanical failures after 10,000km of driving using antilag often.

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"Very creative thinking, what were you drinking?

In R&R protection, the rich is ~10% and the retard ~5 degrees. For any decent anti lag you would need ~30% rich and ~25 degrees retard. That way you would have sufficient unburnt fuel and the exhaust valve would be open when the plug fires.

Launch Control and Anti Lag are 2 different things. Launch control is for limiting the wheelspin."

Ha Ha, yes this was a turps enriched idea.

Thanks for the reply which shows the ecus strategy aint enough to do anything except make a horrible noise.

I understand the difference between launch control and anti lag. I guess for a cruder term I should have said "launch anti lag" as this theory wont work on the run so to speak.

Thanks for the input.

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"Very creative thinking, what were you drinking?

In R&R protection, the rich is ~10% and the retard ~5 degrees. For any decent anti lag you would need ~30% rich and ~25 degrees retard. That way you would have sufficient unburnt fuel and the exhaust valve would be open when the plug fires.

Launch Control and Anti Lag are 2 different things. Launch control is for limiting the wheelspin."

Ha Ha, yes this was a turps enriched idea.

Thanks for the reply which shows the ecus strategy aint enough to do anything except make a horrible noise.

I understand the difference between launch control and anti lag. I guess for a cruder term I should have said "launch anti lag" as this theory wont work on the run so to speak.

Thanks for the input.

i use launch control and antilag system on my gtr r32 and have had a very good run and result so far, i can get between 6 to 8 psi on launch. i do not have rotational idle though but can use that later on if using it for moretrack days, but i need to go single throttle body for that.

also as far as killing engines that depends more on the tuners ability, i have worked with many evo's and a few subie's running very aggressive anti lag settings and 40 percent throttle openings at idle (ecu misfires engine to bring it idle) and they will run a season with these engines.

there are quite a few ways you can have effective anti lag, rich unburnt fuel in the

manifold with hight exhaust temperatures and then adding oxygen creates great impellor drive. i was lucky enough to go for a drive in a wrc car in perth a few years ago and that car was producing 25 psi before dropping the clutch!!!

lots of good theories made whilst drinking, lol

cheers russell

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