How bad is it to run aint lag~~ vid
MY OLD EVO
That was my evo. All that was is the two step. It is different than most of the evo owners that have a two step because my evo had an Autronic stand alone on it. I didn't have much of an rpm drop and that why it cycles so quickly companied to stock ECU 2-steps. I also retarded the timing under the 2-step and added additional fuel. That isn't a true antilag, but has the same general principle. A true antilag cuts spark to different cylinders at random so the excess fuel coming out will combust in the manifold/exhaust housing. Generally cars running antilag have around a 3000 rpm idle. Pay attention to a WRC car it idles high and pops and cracks like crazy. I only used the 2-step when I ran my car at the drag strip once and when auto-xing. Probably less than two minutes total use in the two years I had the evo with autronic on there.
That was my evo. All that was is the two step. It is different than most of the evo owners that have a two step because my evo had an Autronic stand alone on it. I didn't have much of an rpm drop and that why it cycles so quickly companied to stock ECU 2-steps. I also retarded the timing under the 2-step and added additional fuel. That isn't a true antilag, but has the same general principle. A true antilag cuts spark to different cylinders at random so the excess fuel coming out will combust in the manifold/exhaust housing. Generally cars running antilag have around a 3000 rpm idle. Pay attention to a WRC car it idles high and pops and cracks like crazy. I only used the 2-step when I ran my car at the drag strip once and when auto-xing. Probably less than two minutes total use in the two years I had the evo with autronic on there.
i think what we saw in those videos are two steps not anti-lag.
the antilag just keep the boost up between shifts. the easyest way to do it ,they modify the manifold its get fuel injetcted there between shifts and the heat burn it, so the turbo will keep spinning. But this mods are banned out from rally. At least in hungary.
if you want to know more Here is one big help:
http://www.rallycars.com/Cars/bangbang.html
the antilag just keep the boost up between shifts. the easyest way to do it ,they modify the manifold its get fuel injetcted there between shifts and the heat burn it, so the turbo will keep spinning. But this mods are banned out from rally. At least in hungary.
if you want to know more Here is one big help:
http://www.rallycars.com/Cars/bangbang.html
Last edited by Robevo RS; Oct 9, 2007 at 12:22 PM.
Anti-lag:
Exploding gas late in the cycle with a change in timing to expand gas in the exhaust manifold. The expanding gas pushes harder on the turbing (because it is expanding, more exited, and moving faster) and spools your turbo. This can occur when stationary, shifting, or off throttle. WRC cars commonly use all 3. Exploding gas inside your turbine is not great for it and will cause premature failure due to broken blades, worn materials, and may throw it off balance. It also causes extremely high EGT and ruins O2 sensors.
stationary rev limiter/2-step:
A rev limiter that changes so that you can have a stationary rev limiter to build a small amount of boost (less than antilag) and launch at the proper RPM easily. This also serves to protect your engine from damage due to free-revving. Generally, the most damage this will do (when executed properly) is fouled spark plugs.
No lift to shift/3-step:
When shifting, this allows the driver to keep the gas pedal floored. When you push in the clutch it sets a second (or 3rd if you have a stationary rev limiter, hence 3 step) rev limiter lowering RPM, generally to your shift-point. This can be used in combination with anti-lag to maintain more boost, but typically this is not required as keeping the throttle plate open will prevent the blowoff valve from firing and maintain any boost pressure that already exists between the intake manifold and turbo. Using anti-lag in combination with this allows you to actually build boost between shifts as some will drop in the fraction of a second that you are not loading the engine. Sometimes you will hear popping from this as a natural occurrence of cutting spark in a spark-cut type rev limiter system. This is pretty hard on your synchros, but won't necessarily harm your Trans incredibly quickly as long as it is executed properly. It allows you to keep a shift and keep a good corner angle in road racing, but will not allow you to rev match. This will not be an issue if you are using the clutch to slow yourself down without rev-matching, but for this reason it is generally only used for drag racing. (Most WRC cars use sequential transmissions)
Any other questions? Enough with the misinformation already!
Exploding gas late in the cycle with a change in timing to expand gas in the exhaust manifold. The expanding gas pushes harder on the turbing (because it is expanding, more exited, and moving faster) and spools your turbo. This can occur when stationary, shifting, or off throttle. WRC cars commonly use all 3. Exploding gas inside your turbine is not great for it and will cause premature failure due to broken blades, worn materials, and may throw it off balance. It also causes extremely high EGT and ruins O2 sensors.
stationary rev limiter/2-step:
A rev limiter that changes so that you can have a stationary rev limiter to build a small amount of boost (less than antilag) and launch at the proper RPM easily. This also serves to protect your engine from damage due to free-revving. Generally, the most damage this will do (when executed properly) is fouled spark plugs.
No lift to shift/3-step:
When shifting, this allows the driver to keep the gas pedal floored. When you push in the clutch it sets a second (or 3rd if you have a stationary rev limiter, hence 3 step) rev limiter lowering RPM, generally to your shift-point. This can be used in combination with anti-lag to maintain more boost, but typically this is not required as keeping the throttle plate open will prevent the blowoff valve from firing and maintain any boost pressure that already exists between the intake manifold and turbo. Using anti-lag in combination with this allows you to actually build boost between shifts as some will drop in the fraction of a second that you are not loading the engine. Sometimes you will hear popping from this as a natural occurrence of cutting spark in a spark-cut type rev limiter system. This is pretty hard on your synchros, but won't necessarily harm your Trans incredibly quickly as long as it is executed properly. It allows you to keep a shift and keep a good corner angle in road racing, but will not allow you to rev match. This will not be an issue if you are using the clutch to slow yourself down without rev-matching, but for this reason it is generally only used for drag racing. (Most WRC cars use sequential transmissions)
Any other questions? Enough with the misinformation already!
Last edited by fostytou; Oct 9, 2007 at 02:26 PM.
Look at the way he's holding the camera, it's being moved fluidly side to side up until the point of the backfire, at which time it jumps slightly and moves, jumps slightly and moves, jumps slightly and moves, and then the video continues.
Being as it was handheld, it would have been fluid all the way through the video. The video is looped at the point of backfire, and then resumes playing normally.
Looks Fake. At least part of it.
Look at the way he's holding the camera, it's being moved fluidly side to side up until the point of the backfire, at which time it jumps slightly and moves, jumps slightly and moves, jumps slightly and moves, and then the video continues.
Being as it was handheld, it would have been fluid all the way through the video. The video is looped at the point of backfire, and then resumes playing normally.
Look at the way he's holding the camera, it's being moved fluidly side to side up until the point of the backfire, at which time it jumps slightly and moves, jumps slightly and moves, jumps slightly and moves, and then the video continues.
Being as it was handheld, it would have been fluid all the way through the video. The video is looped at the point of backfire, and then resumes playing normally.
Looks correct to me now that I'm on a better screen/audio system. Sounds looped too....
to be more specific:
"Anti-Lag System, ALS, is a system used on mainly turbocharged racing and rally engines to eliminate turbo lag. It was used in the early days of turbocharging in F1 until fuel restrictions made its use unsuitable. Later it became a common feature in rally cars due to the mandated restrictors on the turbocharger inlet. Because of the pressure drop across the restriction, the pressure ratio for a given boost level is much higher and the turbocharger must spin a lot faster to produce the same boost as before. This increases turbo lag significantly compared to unrestricted turbochargers.
An ALS system requires an air bypass, and generally this is done in one of two ways. The first method is to use a throttle air bypass; this may be an external bypass valve or a solenoid valve which open up the throttle 12-20 degrees. This allows air to bypass the closed throttle and to reach the engine. The second method is to use a bypass valve which feed charge air directly to the exhaust manifold.
The throttle bypass/throttle solenoid system is combined with ignition retardation and slight fuel enrichment (mainly to provide cooling), typically ignition occur at 35-45° ATDC. This late ignition causes very little expansion of the gas in the cylinder; hence the pressure and temperature will still be very high when the exhaust valve opens. At the same time, the amount of torque delivered to the crankshaft will be very small (just enough to keep the engine running). The higher exhaust pressure and temperature combined with the increased mass flow is enough to keep the turbocharger spinning at high speed thus reducing lag. When the throttle is opened up again the ignition and fuel injection goes back to normal operation. Since many engine components are exposed to very high temperatures during ALS operation and also high pressure pulses, this kind of system is very hard on the engine and turbocharger. For the latter not only the high temperatures are a problem but also the uncontrolled turbo speeds which can quickly destroy the turbocharger. In most applications the ALS is automatically shut down when the coolant reaches a temperature of 110-115°C to prevent overheating.
An ALS system working with a bypass valve which feeds air directly to the exhaust system can be made more refined than the system described above. Some of the earliest systems of this type were used by Ferrari in F1. Another well-known application of this type of anti-lag system was in the WRC version of the 1994 Toyota Celica GT-Four (ST-205). Four brass tubes fed air from the turbocharger's Compressor Bypass Valve (CBV) to each of the exhaust manifold tracks, in order to provide the necessary air for the combustion of the fuel. The system was controlled by two pressure valves, operated by the ECU. Besides the racing version, the hardware of the anti-lag system was also installed in the 2500 "Group A homologation base WRC method car" street legal Celica GT-Fours. However, in these cars the system was disabled and inactive. The tubes and valves were only present for homologation reasons.
Today's WRC cars also use anti-lag systems which feed air directly to the exhaust system. The reason is that these systems are more refined, more effective with advanced computer control, and also quieter. Today this kind of system has reached such a refinement that it’s even possible to use the system in a road car. A recent example is the Prodrive P2 prototype. The system works by bypassing charge air directly to the exhaust manifold which acts as a combustor when fuel rich exhaust from the engine meets up with the fresh air from the bypass. This will provide a continuous combustion limited to the exhaust manifold which significantly reduces the heat and pressure loads on the engine and turbocharger. With the latest anti-lag systems the bypass valve can not only be opened or closed but it can actually control the flow of air to the exhaust manifold very accurately. The turbocharger is fitted with a turbo speed sensor and the engine management system has a map based on throttle position and car speed which is used to find a suitable turbocharger speed and boost pressure for every condition. When the engine alone can’t provide enough exhaust energy to reach the turbo speed/boost demanded by the management system, the bypass valve opens and exhaust manifold combustion begins. This not only reduces turbo lag, but it also allows boost to be produced at very low engine speeds where boost was previously limited by compressor surge or exhaust energy. With relatively high boost at low speeds, this makes the low end torque superior even to large naturally aspirated engines. The system is quite loud and is banned on some rallies because of the noise it produces."
DOWN SIDE:
"A quick rise of the turbocharger's temperature (which jumps from ~800°C to the 1100°C+ region) whenever the system is activated
A huge stress on the exhaust manifold and pipes (mounted on a street car a bang-bang system would destroy the exhaust system within 50-100 km)
The turbo produces significant boost even at engine idle speeds
The explosions which occur in the exhaust tubes generate important flames which can, sometimes, be seen at the end of the exhaust tube
Reduced engine brake"
"Anti-Lag System, ALS, is a system used on mainly turbocharged racing and rally engines to eliminate turbo lag. It was used in the early days of turbocharging in F1 until fuel restrictions made its use unsuitable. Later it became a common feature in rally cars due to the mandated restrictors on the turbocharger inlet. Because of the pressure drop across the restriction, the pressure ratio for a given boost level is much higher and the turbocharger must spin a lot faster to produce the same boost as before. This increases turbo lag significantly compared to unrestricted turbochargers.
An ALS system requires an air bypass, and generally this is done in one of two ways. The first method is to use a throttle air bypass; this may be an external bypass valve or a solenoid valve which open up the throttle 12-20 degrees. This allows air to bypass the closed throttle and to reach the engine. The second method is to use a bypass valve which feed charge air directly to the exhaust manifold.
The throttle bypass/throttle solenoid system is combined with ignition retardation and slight fuel enrichment (mainly to provide cooling), typically ignition occur at 35-45° ATDC. This late ignition causes very little expansion of the gas in the cylinder; hence the pressure and temperature will still be very high when the exhaust valve opens. At the same time, the amount of torque delivered to the crankshaft will be very small (just enough to keep the engine running). The higher exhaust pressure and temperature combined with the increased mass flow is enough to keep the turbocharger spinning at high speed thus reducing lag. When the throttle is opened up again the ignition and fuel injection goes back to normal operation. Since many engine components are exposed to very high temperatures during ALS operation and also high pressure pulses, this kind of system is very hard on the engine and turbocharger. For the latter not only the high temperatures are a problem but also the uncontrolled turbo speeds which can quickly destroy the turbocharger. In most applications the ALS is automatically shut down when the coolant reaches a temperature of 110-115°C to prevent overheating.
An ALS system working with a bypass valve which feeds air directly to the exhaust system can be made more refined than the system described above. Some of the earliest systems of this type were used by Ferrari in F1. Another well-known application of this type of anti-lag system was in the WRC version of the 1994 Toyota Celica GT-Four (ST-205). Four brass tubes fed air from the turbocharger's Compressor Bypass Valve (CBV) to each of the exhaust manifold tracks, in order to provide the necessary air for the combustion of the fuel. The system was controlled by two pressure valves, operated by the ECU. Besides the racing version, the hardware of the anti-lag system was also installed in the 2500 "Group A homologation base WRC method car" street legal Celica GT-Fours. However, in these cars the system was disabled and inactive. The tubes and valves were only present for homologation reasons.
Today's WRC cars also use anti-lag systems which feed air directly to the exhaust system. The reason is that these systems are more refined, more effective with advanced computer control, and also quieter. Today this kind of system has reached such a refinement that it’s even possible to use the system in a road car. A recent example is the Prodrive P2 prototype. The system works by bypassing charge air directly to the exhaust manifold which acts as a combustor when fuel rich exhaust from the engine meets up with the fresh air from the bypass. This will provide a continuous combustion limited to the exhaust manifold which significantly reduces the heat and pressure loads on the engine and turbocharger. With the latest anti-lag systems the bypass valve can not only be opened or closed but it can actually control the flow of air to the exhaust manifold very accurately. The turbocharger is fitted with a turbo speed sensor and the engine management system has a map based on throttle position and car speed which is used to find a suitable turbocharger speed and boost pressure for every condition. When the engine alone can’t provide enough exhaust energy to reach the turbo speed/boost demanded by the management system, the bypass valve opens and exhaust manifold combustion begins. This not only reduces turbo lag, but it also allows boost to be produced at very low engine speeds where boost was previously limited by compressor surge or exhaust energy. With relatively high boost at low speeds, this makes the low end torque superior even to large naturally aspirated engines. The system is quite loud and is banned on some rallies because of the noise it produces."
DOWN SIDE:
"A quick rise of the turbocharger's temperature (which jumps from ~800°C to the 1100°C+ region) whenever the system is activated
A huge stress on the exhaust manifold and pipes (mounted on a street car a bang-bang system would destroy the exhaust system within 50-100 km)
The turbo produces significant boost even at engine idle speeds
The explosions which occur in the exhaust tubes generate important flames which can, sometimes, be seen at the end of the exhaust tube
Reduced engine brake"
Evolving Member
Joined: Dec 2005
Posts: 251
Likes: 0
From: Connecticut
i love people who think anti-lag is when you're sitting stationary and you're using a 2-step. true anti-lag is when you hear a quick backfire during shifts, and you're boost doesn't drop between shifts. check this out:
Rally STi w/true anti-lag
watch the whole video. the tephra no-lift-shift mod is the closest to this you'll come without blowing your turbo after 10k miles.
-Chris
Rally STi w/true anti-lag
watch the whole video. the tephra no-lift-shift mod is the closest to this you'll come without blowing your turbo after 10k miles.
-Chris
Last edited by evo_what; Oct 10, 2007 at 05:10 PM.
Evolving Member
Joined: Dec 2005
Posts: 251
Likes: 0
From: Connecticut
-Chris