anti-lag?
 

Gents

what with the amount of large turbos on this forum
I was wondering has anyone experimented with using a really late GDi timing and spark retard to give in essence anti-lag and so spool the turbo up.


its something more and more OEM's are using as rather bizarrely if you don't give it a lot of fuel you end up very very lean about lambda 1.3 and this doesn't contain enough fuel to burn hot so its not like the anti-lag of old where things all melt

the BMW engines all do this which is why they can get 250+ ft/lb at 1500rpm on their turbos

your thoughts?

One of the more well known tuners James Martin has done something like this on stock ecu. Unfortunately, he is banned here

[ame="https://www.youtube.com/watch?v=JPskKzBy6mY"]FRS antilag - YouTube[/ame]

i was making about 10psi off the line on a precision 5858 with ecutek launch control

Yes with launch control though you hold a high rpm so 4000rpm?

I'm more interested in a normal driving situation where you just roll on the throttle at low rpm

The high compression ratio of the FA20 helps spool up the bigger turbos so there isn't a great need to play with this stuff. You cruise at about 2.5k so boost at lower RPMs isn't needed.

That being said, I'm going to implement a rally style ALS later this year. Just for the sound :-D

Why is James Martin banned?

Is this similar to a stutter box?

its more to get a big engine feel really, you're right in saying that you don't 'need' the boost at 2.5K but its like having a 3.5ltr v6 instead of a 2.0ltr 4 you can be tickling along at 1500rpm and just roll on the throttle and it pulls hard

so no-one apart this fellow who's banned?

I'm interested. You have my attention.

:popcorn:

If you have anything you'd like to try, I have a tuning device and an engine I'm willing to blow up.... I mean, experiment with.

Coincidentally, this motor has sodium-filled exhaust valves from the factory, so they're very temperature tolerant... The GDI seals are not.

I worry a little about detonation at Lambda 1.3 and any boost though... The late timing should help, but then I'm not following where all the torque is supposed to be coming from if you back the timing off that much... If you transition back to traditional timing/fueling at low RPM, I'm liking the chances of transient detonation during the transit, and you'll likely lose any turbo spool you had...


I'm not arguing, I'm musing. I'm curious, but I'm afraid it's beyond my tuning knowledge.

I see in the Martin youtube video he passes 5 PSI pretty early, but not 1500 early, more like 25-27..

Video earlier is not anti-lag. That looks like launch control.

The reason street cars don't use anti-lag is because it destroys everything. Rally cars use it for increased transient response from on/off throttle applications.

Making it crack/pop on decel is one thing (not anti-lag), true anti-lag kills everything quickly.

the 1st thing to try is just going for a really late Gdi timing?
So try about 150 degrees later than normal this will produce odd lambda readings due to the post combustion but you should also see a positive increase in boost

Something about the Admins being Nazis or something like that

I am in for results :popcorn:

Who's testing this concept?

Any further development???