General cinq/sei turbo FAQ
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General cinq/sei turbo FAQ
beastyjay
Banned
Re: THE cinq turbo faq.
good valve is it?
good valve is it?
Re: THE cinq turbo faq.
Im not sure that a dump valve will help with lag. That's there to prevent the turbo stopping very quickly when you shut the throttle, it allows the turbo to keep spinning (and reduces wear to the bearings).
The only way you can reduce lag (that I know of) is to use a smaller turbo, say a Garrett GT17 in place of the T2
Im not sure that a dump valve will help with lag. That's there to prevent the turbo stopping very quickly when you shut the throttle, it allows the turbo to keep spinning (and reduces wear to the bearings).
The only way you can reduce lag (that I know of) is to use a smaller turbo, say a Garrett GT17 in place of the T2
Re: THE cinq turbo faq.
A dump valve can reduce lag between gears as it keeps turbo spinning as Arse said, and of course a recirculating is supposed to ensure this by feeding unused boost back into the system in front of the turbo, but it can't reduce lag when cruising along and stamping on the gas.
I know tha whoel piont of the GT15 in the Van Aaken kit is supposed to be for minimum lag as its spins up quick, which it does to a pretty good degree, i just know from my R5GTT days its was laggy as standard but modern turbo technology has moved on lot recently and you can get quicker spinning up turbos now.
A dump valve can reduce lag between gears as it keeps turbo spinning as Arse said, and of course a recirculating is supposed to ensure this by feeding unused boost back into the system in front of the turbo, but it can't reduce lag when cruising along and stamping on the gas.
I know tha whoel piont of the GT15 in the Van Aaken kit is supposed to be for minimum lag as its spins up quick, which it does to a pretty good degree, i just know from my R5GTT days its was laggy as standard but modern turbo technology has moved on lot recently and you can get quicker spinning up turbos now.
Re: THE cinq turbo faq.
Seems a job for anti lag but where it would fit is beyond me, apart from that though the work and car is excellent.
As not to ruin the FAQ I will start a new thread on this particular subject and ask for the posts to be copied over.
Liam
Seems a job for anti lag but where it would fit is beyond me, apart from that though the work and car is excellent.
As not to ruin the FAQ I will start a new thread on this particular subject and ask for the posts to be copied over.
Liam
Re: THE cinq turbo faq.
Anti LAg System or ALS explained.
As you might be aware of, turbochargers display what is known as lag time which is the time needed for the turbine to reach its full throttle from an intermediate rotational speed state. The duration of a turbocharger's lag depends on many factors among which its inertia, airflow efficiency, back pressure, etc. The problem is partly dealt with by fitting a turbo dump valve, which acts each time the driver lifts his foot from the throttle. The dump valve will evacuate the pressurized air coming out of the turbocharger while the inlet manifold is closed thus allowing the turbine not to stall and avoiding possible damage to its bearings. In race cars it is very common to fit oversized turbochargers in order to be able to produce enough boost pressure and assure a sufficient engine output. Big turbochargers display significant amounts of lag due to their increased rotational inertia. In such cases the dump valve is insufficient to allow the turbocharger not to loose too much speed when the driver lifts off. Additionally rally cars hold a turbo restrictor, which is regulated by the FIA. One of the restrictor' effects is to increase lag time. This is why in racing cars, and more specifically in rally cars, where torque and engine availability are critical factors, most applications use anti-lag systems.
During lag time the engine is much less responsive and its output well below nominal. To counter the effect of the turbocharger's lag time drivers used to anticipate the engine's reactions by accelerating well before they would have done in a non-turbo car. Others have used a technique, introduced by the German driver Walter Röhrl, known as "left foot braking" where the driver uses his left foot to brake the car while his right foot accelerates to keep the turbocharger in optimal load. Left foot braking is very hard on the brakes which are put into extreme stress but is very efficient in keeping the turbo spinning.
ALS was a simple idea but one that was relatively difficult to implement. Only when electronic engine management systems were advanced enough to allow taking into consideration many more parameters than in the past it became possible to use them efficiently in handling ALS. To the best of my knowledge Toyota Team Europe were the first to use it in racing (Toyota's implementation is known as Toyota Combustion Control System while Mitsubishi call the system Post Combustion Control System).
So what is it?
When the driver lifts his foot from the gas pedal the ignition timing is altered with sometimes 40° or more of delay (retard) and the intake air and fuel supply mixture is made richer. The inlet butterfly is kept slightly open or an air injector is used to maintain air supply to the engine. This results in air/fuel mixture that keeps getting in the combustion chambers when the driver no longer accelerates. The ignition being delayed, the air/fuel mixture reaches the exhaust tubes mostly unburned. When the spark plug fires, the exhaust valve is starting to open due to the ignition delay mentioned above. Additionally, the exhaust temperature being extremely high, the unburned fuel explodes at the contact of the exhaust tubes. Luckily the turbo sits right there and the explosion keeps it turning (otherwise it would slow down since its intake, the exhaust gases, is cut-off). The effect is vastly lower response times with some downsides:
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
The ALS effect is mostly dependent on the air allowed into the engine, the more air supplied the more the ALS effect will be noticeable. Consequently ALS systems can be more or less aggressive. A mild ALS will maintain a 0 to 0.3 bar pressure in the inlet manifold when activated whereas, when inactive, the pressure in the inlet manifold with the throttle closed would be in the region of -1 bar (absolute vacuum). Racing ALS versions can maintain a pressure of up to 1.5 bar in the inlet manifold with the throttle closed.
While the systems mounted in Toyota and Mitsubishi racing cars are relatively smooth and noiseless those fitted in Ford and Subaru cars are much more noisy and aggressive.
The bang-bang system owns its name to the loud explosion noises one hears whenever the driver lifts off. Most racing implementations have user selectable anti-lag settings depending on the terrain, usually three settings can be selected by the driver going from mild to very aggressive.
Aaron.
Anti LAg System or ALS explained.
As you might be aware of, turbochargers display what is known as lag time which is the time needed for the turbine to reach its full throttle from an intermediate rotational speed state. The duration of a turbocharger's lag depends on many factors among which its inertia, airflow efficiency, back pressure, etc. The problem is partly dealt with by fitting a turbo dump valve, which acts each time the driver lifts his foot from the throttle. The dump valve will evacuate the pressurized air coming out of the turbocharger while the inlet manifold is closed thus allowing the turbine not to stall and avoiding possible damage to its bearings. In race cars it is very common to fit oversized turbochargers in order to be able to produce enough boost pressure and assure a sufficient engine output. Big turbochargers display significant amounts of lag due to their increased rotational inertia. In such cases the dump valve is insufficient to allow the turbocharger not to loose too much speed when the driver lifts off. Additionally rally cars hold a turbo restrictor, which is regulated by the FIA. One of the restrictor' effects is to increase lag time. This is why in racing cars, and more specifically in rally cars, where torque and engine availability are critical factors, most applications use anti-lag systems.
During lag time the engine is much less responsive and its output well below nominal. To counter the effect of the turbocharger's lag time drivers used to anticipate the engine's reactions by accelerating well before they would have done in a non-turbo car. Others have used a technique, introduced by the German driver Walter Röhrl, known as "left foot braking" where the driver uses his left foot to brake the car while his right foot accelerates to keep the turbocharger in optimal load. Left foot braking is very hard on the brakes which are put into extreme stress but is very efficient in keeping the turbo spinning.
ALS was a simple idea but one that was relatively difficult to implement. Only when electronic engine management systems were advanced enough to allow taking into consideration many more parameters than in the past it became possible to use them efficiently in handling ALS. To the best of my knowledge Toyota Team Europe were the first to use it in racing (Toyota's implementation is known as Toyota Combustion Control System while Mitsubishi call the system Post Combustion Control System).
So what is it?
When the driver lifts his foot from the gas pedal the ignition timing is altered with sometimes 40° or more of delay (retard) and the intake air and fuel supply mixture is made richer. The inlet butterfly is kept slightly open or an air injector is used to maintain air supply to the engine. This results in air/fuel mixture that keeps getting in the combustion chambers when the driver no longer accelerates. The ignition being delayed, the air/fuel mixture reaches the exhaust tubes mostly unburned. When the spark plug fires, the exhaust valve is starting to open due to the ignition delay mentioned above. Additionally, the exhaust temperature being extremely high, the unburned fuel explodes at the contact of the exhaust tubes. Luckily the turbo sits right there and the explosion keeps it turning (otherwise it would slow down since its intake, the exhaust gases, is cut-off). The effect is vastly lower response times with some downsides:
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
The ALS effect is mostly dependent on the air allowed into the engine, the more air supplied the more the ALS effect will be noticeable. Consequently ALS systems can be more or less aggressive. A mild ALS will maintain a 0 to 0.3 bar pressure in the inlet manifold when activated whereas, when inactive, the pressure in the inlet manifold with the throttle closed would be in the region of -1 bar (absolute vacuum). Racing ALS versions can maintain a pressure of up to 1.5 bar in the inlet manifold with the throttle closed.
While the systems mounted in Toyota and Mitsubishi racing cars are relatively smooth and noiseless those fitted in Ford and Subaru cars are much more noisy and aggressive.
The bang-bang system owns its name to the loud explosion noises one hears whenever the driver lifts off. Most racing implementations have user selectable anti-lag settings depending on the terrain, usually three settings can be selected by the driver going from mild to very aggressive.
Aaron.
Re: THE cinq turbo faq.
To chevaler:
Does 1.2 16V engine fit to 1.1FIRE 8V transmission and clutch? is clutch from 16V (190mm diameter) or standard 180mm ? How big problem was with new electricity? I mean to connect it with original cinque.
Thanks.
P.S..: perfect job. I am very "hungry" for time on 1/4mile.
To chevaler:
Does 1.2 16V engine fit to 1.1FIRE 8V transmission and clutch? is clutch from 16V (190mm diameter) or standard 180mm ? How big problem was with new electricity? I mean to connect it with original cinque.
Thanks.
P.S..: perfect job. I am very "hungry" for time on 1/4mile.
chevaler
New member
- Joined
- Oct 31, 2005
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Re: THE cinq turbo faq.
All transmition is the original cinque ones.
The 1.2 16V could be plug!
After, maybe you will have a problem with 1.2 16V electrical pluggin on cinque!
We have use the 1.1 8v cables connected on cinque with the new electrique cables of our new injection system.
We are changing our fuel pump which have a to small debit!
After we will restart our test.
I will say you when i will have a time on 1/4 miles!
Regards,
All transmition is the original cinque ones.
The 1.2 16V could be plug!
After, maybe you will have a problem with 1.2 16V electrical pluggin on cinque!
We have use the 1.1 8v cables connected on cinque with the new electrique cables of our new injection system.
We are changing our fuel pump which have a to small debit!
After we will restart our test.
I will say you when i will have a time on 1/4 miles!
Regards,
Last edited:
Re: THE cinq turbo faq.
Fuel pump is not problem. I have one from Uno Turbo. So Clutch and transmission will fit. That are good news for me) I will buy this little dragon:
Clicky here to view
and Engine I can have now. Only wires and ECU are missing. I will take detailed photos on rebuilding to inspirate others. Finally I will not have turbo installed, Only 1.2 16V engine but with some upgrades - to reach 100PS/150N.m. Then I should reach 15.5s to 1/4mile. :worship:
Regards
Fuel pump is not problem. I have one from Uno Turbo. So Clutch and transmission will fit. That are good news for me
) I will buy this little dragon:Clicky here to view
and Engine I can have now. Only wires and ECU are missing. I will take detailed photos on rebuilding to inspirate others. Finally I will not have turbo installed, Only 1.2 16V engine but with some upgrades - to reach 100PS/150N.m. Then I should reach 15.5s to 1/4mile. :worship:
Regards
Re: THE cinq turbo faq.
Sorry to say but i am not convinced about 15.5s 1/4's, my turbo cinq running ~110bhp with ~150nm will only run mid-low 16's, possibly high 15's on a very cool dry day does sound nice though and still nothing to laugh at :devil:
ReproBoy said:
Sorry to say but i am not convinced about 15.5s 1/4's, my turbo cinq running ~110bhp with ~150nm will only run mid-low 16's, possibly high 15's on a very cool dry day
does sound nice though and still nothing to laugh at :devil:
Re: THE cinq turbo faq.
But by eck that would be nippy!
I want that one!
But by eck that would be nippy!
I want that one!
TurboCinqy1250
Member
Re: THE cinq turbo faq.
With a light overweighted Cinq it's still difficult to get the car under the 16 sec with 2 persons and 120WHP 178Nm.
With a light overweighted Cinq it's still difficult to get the car under the 16 sec with 2 persons and 120WHP 178Nm.
TurboCinqy1250
Member
Re: THE cinq turbo faq.
@ Jeevo
Anti LAg System or ALS explained.......
I've just read the ALS story and I'm very interest in it.
I always want to have flames out of my exhaust without using a flame kit. And I was for 100% sure that a highly tuned car was able to get this...but untill know...almost no flames and bangs
How bad is it for the engine, valves, turbo and a open exhaust when I'm using it in the mild version?
I think I can set the 2nd injector with no/low deflection to give some fuel and at the same time the whole ignition row (also no deflection/closed TB) (except the rpm area between 600 and 1500/2000) at that point at retard timing.
@ Jeevo
Anti LAg System or ALS explained.......
I've just read the ALS story and I'm very interest in it.
I always want to have flames out of my exhaust without using a flame kit. And I was for 100% sure that a highly tuned car was able to get this...but untill know...almost no flames and bangs
How bad is it for the engine, valves, turbo and a open exhaust when I'm using it in the mild version?
I think I can set the 2nd injector with no/low deflection to give some fuel and at the same time the whole ignition row (also no deflection/closed TB) (except the rpm area between 600 and 1500/2000) at that point at retard timing.
TurboCinqy1250
Member
Re: THE cinq turbo faq.
Oke it's working but those big bangs are not the thing i've wanted.
Only the flames.
Yesterday on the highway I was testing this setup and suddenly I heard a little bang. And the car behind us immediately flashes with his lights
After that we went to a industy place and I try to capture it on film
And this is what we saw.
http://members.lycos.nl/turbocinqy/forums/HT-Cinqboom.WMV
http://members.lycos.nl/turbocinqy/forums/HT-Cinqboom2.WMV
Mayyyyyybe a little to loud
But I proved that when you set youre ignition 15 degrees retarded and spray some fuel that you get big banges without flamekit
Oke it's working but those big bangs are not the thing i've wanted.
Only the flames.
Yesterday on the highway I was testing this setup and suddenly I heard a little bang. And the car behind us immediately flashes with his lights
After that we went to a industy place and I try to capture it on film
And this is what we saw.
http://members.lycos.nl/turbocinqy/forums/HT-Cinqboom.WMV
http://members.lycos.nl/turbocinqy/forums/HT-Cinqboom2.WMV
Mayyyyyybe a little to loud
But I proved that when you set youre ignition 15 degrees retarded and spray some fuel that you get big banges without flamekit
OP
OP
Re: THE cinq turbo faq.
and a not long to live exhaust?
and a not long to live exhaust?
TurboCinqy1250
Member
Re: THE cinq turbo faq.
I almost don't have any exhaust. Only a mod rear damper. 60mm pipe with a few holes.
I almost don't have any exhaust. Only a mod rear damper. 60mm pipe with a few holes.
Re: THE cinq turbo faq.
Anti lag rips through your turbo. Unless u have deep pockets and lots of spare time dont do it!
As for reducing lag, us coupe boys have spool ups as low as 2200rpm on standard turbos, because we increase the diameter of the downpipe and also fit a straight induction pipe which increases the airflow in. I run the gt28r and i spool up about 2500rpm (still to be tested on RR)
Technically u guys could use the same ideas and reduce spool up time!
Ross
Anti lag rips through your turbo. Unless u have deep pockets and lots of spare time dont do it!
As for reducing lag, us coupe boys have spool ups as low as 2200rpm on standard turbos, because we increase the diameter of the downpipe and also fit a straight induction pipe which increases the airflow in. I run the gt28r and i spool up about 2500rpm (still to be tested on RR)
Technically u guys could use the same ideas and reduce spool up time!
Ross
