Stinger 4424 ECU tuning...

[cat007]

Has anyone tuned their cars with the EMS stinger 4424 just on normal roads?

I did have the car tuned on a dyno but that was a few years ago and after sitting for a couple of years and changing the wastegate it's no longer performing all that well. It appears to be running super rich. I've had the injectors cleaned and tested so perhaps that's where the extra fuel is coming from.

Trying to use the tune analyser part of the software and it's tricky to get all the cells populated. I'm guessing you have to use the brake a bit?

What are others experiences?

[QikStarlie]

i take it you have a wideband to check it with?

you'd be better off to try track down the reason its changed rather than trying to retune.

you changed the wastegate. same boost or?
injectors shouldn't have changed just becuase they were cleaned, unless they had issues when it was first tuned.

no other changes?

a lot can effect the tune. one thing that alot of people overlook is the vac/boost lines. most importantly to map sensor & fuel pressure regulator. even if you move the line to a different place on the inlet manifold it can have a big effect on what pressure they see, which will = lean or rich.

cant help with ecu specific stuff. as haven't had anything to do with stingers

[cat007]

Thanks for that.

Yeah using an innovate LC-1 wideband.

I have a feeling the fuel pressure has been raised a little. I had to wind the FPR out and replace an O ring a while back - after it was tuned. I stupidly didn't take note of the fuel pressure before at idle. I set it to 40psi which is what I 'think' it was before.

Basically it's running very rich all throughout the rev/boost range.

I haven't change anything else - just the wastegate and have also plumbed it back into the exhaust. Previously was venting to atmosphere.

There's nothing else that's changed that I can think of.

Boost is down from about 16psi to 12psi - mainly because I haven't had a chance to plumb in the EBC.

Vac lines to ECU (has onboard map sensor (which is a bad design IMO)), FPR and pretty much everything else are the same.

Thanks again.

[cat007]

Oh I forgot to mention I blocked off the crank case breather from the throttle body. It used to have a port that would scavenge the crank case. This port was between the throttle body and the head - in the highest vacuum area I'm guessing.

Also there's what appears to be some sort of idle adjuster screw. When you unscrew it, it allows air to bypass the throttle butterfly increasing the idle speed. Leaning her out a bit I guess. This has also been adjusted so I can't remember if this is supposed to be screwed in or out.
I wouldn't imagine this would allow enough air through when driving along to cause any weird rich/lean circumstances....?

[QikStarlie]

i'd just wind down the fuel pressure till the afr is correct. 11.5 - 12afr under boost. then check if the cruise afr has also come right. if it has your good to go

just back it off a few psi at a time to start with. as a small pressure change can make quite a difference. note down what you end up with, and check it every now and then. as alot of aftermarket regs tend to walk over time


edit: that stuff in you last post shouldn't have much effect if i read it correctly. try as i said above ^

[cat007]

What should I aim to get my idle air fuel ratio at?

I've got her idling pretty perfect at about 14.4-14.8.

Will take her out tomorrow and play with the cruise settings then make sure she's about 12:1 when on boost?

I'm aware that any advice given if my engine blows up I won't say it's your fault....

[QikStarlie]

yeh sounds good for idle. some engines will idle junk that lean but if it runs good there leave it.

light load cruise around 15 is usually good. try stay away from anything under mid 14's

turbo i usually tune under 12afr. 11.8 or something under boost gives bit of a safety buffer, can run leaner but wont gain bugger all if anything.


most important thing is timing. make sure base timing is set correct, to what it was when it was dyno tuned. if you have touched the cas or anything.

if it were me i would pull 5-10 degree out of the whole map. then put it back to how it was, once afr correct.

[cat007]

Should I tune the idle with the idle speed valve fully closed or fully open or somewhere in the middle?
It runs perfect when hot, although if it's been sitting for about 10-15 mins after a good run, it won't idle that well, actually it's about the same when stone cold too. Have to crank it for a bit to get it to run.
Problem is if I wind the idle speed valve out a bit so it idles faster when cold, it idles about 1200rpm when hot....