AlexE

Some of my drag racing dsm friends use a feature that keeps their turbos spooled at idle similar to what rally cars do.... he is able to keep 15-18 psi at IDLE.

The systems retard the ignition while cranking AF into a super rich condition.... so in essence unburnt fuel is thrown in to the exhaust igniting it and keeping the turbo spooled..... it also initiates this sequence on every shift...

Its not meant for daily driving but for drag racing.... but I am curious if this could be applied to our setups for track use.... According to the dsm owners it has negligible wear on drag racing apps.

Has anyone had any experience using this setup on the track ??

robthe54

negligible is relative here...
some dragsters don't get 5 miles before they need to be rebuilt...


if you want to kill lag, upgrade your turbo... aerodyne makes some nice "zero lag" units

plus, you're not even bothering to think about the differences in whats going on... dragsters are faster in automatic, b/c
auto tranny's use a torque converter which is basically a clutch that uses fluid and fans... (doesn't wear like a clutch) the TC has something called a "lock up speed" which is the speed where engine speed = tranny input speed...

ALOT of turbo'd dragsters run converters that DON'T lock up... they just slip less and less

bottom line... you drive a porsche, not a mistsu, you drive on the road course, they go in a straight line...

...apples and oranges

eman930

I have heard about this a long time ago on a Pelican post, From what I remember it will do a number on your exhaust system and turbo, Its almost likea afterburner, The rich A/F mixture is burning in the exhaust header not the combustion chamber. Iw ould do it the right way like Robthe54 said and upgrade the turbo and intercooler it might cost some money but it will give you one sweet setup

thesmokingman

Anti-Lag has been around for a long time and is pretty common on rally cars. It's purpose is to keep the turbo spooled off throttle, which is incredibly useful on a rally car as they often negotiate slow corners and its finding its way onto many a drag car for the very same principles.

I haven't used it on a drag strip, but its have seen it in action at Rim of the World and other events.

Also, it does not damage anything. There have been no turbos burned, nor engine fires, nor any such nonsense that I've witnessed. It appears to be quite popular down under on the street scene too. Fears of damage stem from not having experience with doing it right.

However, I'd say that twinscroll turbo systems would help the 951's much more on a reality scale.

Download this for fun, you hear the anitlag in action:
http://www.ravensblade-impreza.com/d...powerslide.zip

Mark-87-951

Those aerodyne turbos sound good but I wonder what the cost would be? $$$

Mark

NZ951

The Link computer has two antilag functions one uses a solenoid pretty clever, but I dont really need it. Well, not yet.

Mark-87-951

NZ951,

how does the solenoid work for anti-lag and what is the other anti-lag function?

Mark

thesmokingman

I don't know that Link Wire-In EMS had antilag capabilities, I thought its only on the Plug-In EMS' and is a custom software option.

But seriously, you wouldn't want to be driving around on the street with antilag enabled. Its gotta be the most annoying sound to ears that aren't educated to what their ears are being assaulted by. Chirp, chirp, cheeep cheeep, rawwwr, whoooosh, over and over again. Hehe.

rage2

most standalones have anti-lag features. Just remember that rally cars use this, and they replace and rebuild their turbos after several stages. Expect the same life if you use anti-lag .

Mike Murcia

When Huntley was around, he told me that they were accomplishing the antilag by placing a fifth fuel injector in the exhaust, but it was a track only option. I think most systems like the Link have controls for a separate injector for either water on the intercooler, alcohol, gas, or whatever else you can imagine.

Laust Pedersen

"some dragsters don't get 5 miles before they need to be rebuilt..."

How about 1/4 mile between rebuilds for top fuel dragsters or put in another way 500 (full power) engine revolutions between teardowns (5 sec @ 6000 rpm). How is that for reliability?

thesmokingman

Thats an interesting take on ALS. However, I'd just stick to the original design by Toyota, or the newer EGR system.

ALS, or Anti-Lag Systems retard the ignition timing so unburned fuel passes through the engine and, instead of igniting in the engine, ignites in the exhaust manifold upon contact, and spins the turbo over.

The air needed for this combustion is provided by the standard throttle body, which is opened to a greater extent than normal whilst anti-lag is running...thus the reason it has a solenoid to keep the throttle open

The ECU uses an idle control sequence so that once you've set the target idle speed, the anti-lag will cut a spark in a rotational sequence with each cylinder, which is why they idle so lumpy, and thus the reason its called rotational idle. If there was no rotational idle, the engine wouldnt idle at all, because the throttle is so far open that the engine would just rev.

The theory is, as soon as you open the throttle, you have full boost and no lag. What I described is Subaru's method as its whats typically done to my WRX and is the standard implementation in our EMS systems.

http://www.rallycars.com/Cars/bangbang.html

And as for reliability, I've heard of street cars running in excess of a few years with no problems. Now I'm not saying go out and run ALS, but if it were that bad I don't see how privateers could afford to race in Grp N?

Now the way to kill a turbo with ALS, is by the exhaust valves and exhaust manifolds reaching excessive EGTs and the only way you can make an EGT excessive with antilag, is to rev it out at high rpm and back off the throttle, and throw flames for minutes at a time, which no one in their right mind would do anyway...

Apart from that, even though the turbo is boosting more often than normal, the mixtures are incredibly rich, meaning the EGTs will not get excessively high in normal use. Also, with systems such as the Pectel T6 and the Ecutek, you can set user programmable disable points and to watch your EGT's and prevent over heating of the turbo.

Again, I've never read of, heard, or witnessed a turbo dieing because of ALS. Also, any decent ECU worth anything would have an engage/disengage trigger, such as the ones I've mentioned including the Motecs.

*BALISTC*

Danno

AlexE, I can program anti-lag into the DME chips. Developed it by accident when some customers requested "extra flames" on shifts...

Not sure how much it helps on the road-course tracks as we're typically running in the upper-RPMs where turbo-lag is really minimal anyway...

But for drag-racing, trying to generate max-boost from idle does take a fraction of a second and would affect 0-60ft times adversely. The other trick used here is the two-step rev-limiter that lets you set an intial rev-limit of say... 4000rpm where you can just floor the car initially to generate some boost in neutal. Then this boost can be carried over when you let up the clutch to launch.