4AGE Anti-Lag setup!!

[mattias]

That picture is from MegaTune.

F1 for help in the dialog might not help in VemsTune, so start here :
http://www.vems.hu/wiki/index.php?page=MembersPage%2FGaborRacz%2FNewAlsLaunchAndOthers

Better and more updated documentation would be great, but this function is not easy to explain or use.

[Sukhoi]

Hi again,

I was wondering what is the max safe retard I can go with when using ALS and Launch Control!?
In my Base Setup -> Ignition Settings -> Ignition Retard Clamp is set to -10 can I go with more retard? like -15 or -25? would it be mechanically harmful to the engine except the higher heat?

Thanks In advance guys

[GintsK]

IMHO it depends only from EGT and MAP. At deceleration MAPs you can go more retarded than at MAPs where engine gives some power. Also remember that we have relative retard to ignition base MAP.
So if you have 40deg in ign map and retard is 50deg, result will be just -10deg.

You can keep control over EGT by adding more fuel. I have somewhat like 950degC and 980 safety switch-off. Sensor right before turbo. Sensor tip extended 12...15mm from wall. Subaru and Audi.

Also there is setting called retard clamp - it is absolute value limiting max possible retard.

[Sukhoi]

Thanks GintsK

Exactly that what I wanted to know the retard clamp, now I set it to -15 while it was -10, and the engine now is building boost
I did my best settings to get 0 vacuum, as am very conservative about this engine regarding heat, specially its gonna be used on track, so ALS will be used for at least 3 min (not little time in my opinion), the max heat I got was 650C and am happy with this this all happen with 3500RPM, didnt need to open the throttle for more, as I managed to build 0.3 Bar with extra more throttle open, but I set it back to 3500, 0 vacuum was a very good point, plus it got sweet rumbling bangs, not high and loud, but fair regarding the result

Thanks all for your help, I appreciate it

[GintsK]

650C - it means your sensor is mounted in wrong place.
You should see far more even with ALS off. Somewhat 840-900deg or even more depending how hard turbo is loaded.

[Sukhoi]

Yes I know, its mounted at the end of the down-pipe, like 40cm far from turbo, I know its not the best location, but from that reading and my reading while cursing I found that that 500-600 is normal operation temp for my engine (based on the location), so, I dont want to exceed it that much, I can build more boost with more retarding now, but for now this is 100% fine with me

Edit: am going to work soon on new setup, 2 EGT first in collector before turbo, and other after turbo, by that I will get more accurate readings

[GintsK]

Using post turbo EGT is hard to get idea about pre turbo temperatures. Just because there is unmeasured component - pressure before turbo. As we know - pressurized gas is hotter.

[Sukhoi]

I will keep this in mind

[rob@vems.co.uk]

The turbine saps heat energy, a good rule of thumb is ~200C drop between pre and post turbo.
But, the thermal mass of the turbine and enclosure results in a time lag of the readings and dampens out the fluctuations, so you never see the minima and maxima temperatures.
From my understanding the only use that a post-turbo EGT sensor has is to ensure that the Catalytic converter isnt going to be overheated.

[Sukhoi]

Just wanted to know what is the max safe EGT temp that i can expect when its located before turbo? for sure the engine is aluminum head!
and what is the temp that i should not go over with?

[rob@vems.co.uk]

Unfortunately it depends - there's not an equivalent of Lambda 1 for EGTs.
You may see peaks of over 1000c at high loads - this is way past aluminium's melting point, but you need to bear in mind that each cylinder will only see those temperatures for about a 1/4 of the time.
Measuring your EGT will allow you to tune the ignition so that you can find the compramise between boost, MBT, EGT and Fuelling.

For more info check http://195.159.109.134/vemsuk/forum/index.php/topic,97.0.html and look for "Calibrating the Ignition Map - Finding MBT"