4AGZE Turbo conversion on stock ECU and AFM. Leaning out.

[Bowlsclubboy]

Hey guys, mate of mine has a early model AFM equipped 4agze in his hachi. It is now equipped with a T25 running stock boost.

When on the dyno, it starts to lean lean out at around 6000rpm.

We're wondering what the best method for controlling this is before the need to goto aftermarket ECU.
We're assuming that the AFM is maxing out and cannot read any more air, so therefore allows no more fuel. If this IS the case, there is no other option but aftermarket is there?

So far the options seem to be:
-Lower pressure wastegate spring, possibly 4lb if available.
-SAFC or Jaycar Fuel adjuster. (may have 440cc injectors available to use with this)
-Restricting inlet size (as a temporary measure, the car is due to drift on the 5th!).
-Extra injector in front of throttle body.
-Using a rev limiter device to cut it at 6...although this would cripple a hachi.

Thanks for your help in advance guys, need answers quick though!

Cheers,

Troy

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[Vios-GT_07]

hm..

i assume u mean running stock boost levels of the GZE's supercharger? if that's the case it shouldn't be leaning out... i wouldn't worry about the boost levels then..

yea SAFC or Jaycar is a good option.. you shouldn't need to go 440cc injectors unless u're chasing higher than stock boost.. possibly also the most cost effective imo, as it can richen the high revs. what's the A/F ratio at the high rev where it leans out? pretty sure the stock injector can support a bit more boost than stock.

restricting the inlet..erm.. with the turbo and going for competition i wouldn't advise it..

extra injector in front of throttle body.. sounds like a plausible idea... just activate it during high revs?

oh don't limit the revs mate, rather get it tuned it properly!

did you consider getting a bigger fuel pump? VL, walbro 195lph? or GSS341 (255lph)?

[old_mr2]

I believe feral4mr2 is running his AFM gte without ECU upgrade, and his hammers, without a leanout.

[feral4mr2]

indeed, 12psi for years of thrashing with stock 4agze ecu, afm, 365cc injectors etc. but i do have a good w2a i/c set-up too.

never had it on a dyno at 12psi, but i'm sure if it was leaning out i should of fooked something ages ago i would think. i do use all the rev range.


what i/c is your mate useing? 440cc injectors would probably help, but then the stock 365cc ones work fine for me??

[YLD-16L]

It must have an issue somewhere as my AFM 4AGZE ran a T28 on ~14.5psi with stock ECU and stock injectors perfectly fine. It was actually slightly rich through the whole RPM range.

You can't just fit 440cc injectors while using the stock ECU, it does not work. We tried it just for interest sake to see how shit it would run. It was driveable but like a pig.

Is your fuel pump and/or fuel pressure regulator doing the job and up to the task?

[Bowlsclubboy]

We did a heap of research last night and found noone else had experienced this with a 4AGTE. The fuel pump is a Bosch unit, the next size up from VLT and fuel lines are 8mm from memory. So it either comes down to a faulty fuel pump or a dodgy AFM I suppose.

It never had this problem with the blower of course, made about 100kw atw i think.

Thanks for your input guys

[YLD-16L]

What's the base fuel pressure?

Is it using the stock FPR?

Has anyone "fiddled" with the AFM in the past (check to see if the access plate looks like it has been resealed).

[Duk]

Prolly to late, but I tripped over this thread after I was piss farting around with my SC MR.
2 things I found with the airflow meter 4agze’s are.
1: The standard airflow meter is way to damn small and will quickly get maxed out in it’s voltage output!
2: The factory computer doesn’t pay much (any!) attention to the airflow meter when it’s in the business end of making power. That is, a SAFC/Jaycar interceptor won’t make much (any) difference to changing air/fuel ratio at the top end.
I found this out when I put my standard circuit board and air temp sensor into a bigger, airflow meter housing and got it to run right with the Jaycar interceptor, but couldn’t get it to run any leaner than standard.

[Bowlsclubboy]

Sorry i forgot to finalise this problem!!

It turned out to be the small fuel buffer (mushroom thing) on the fuel rail, was flowing 2/3rds of f all. He replaced it with another second hand one and problem solved. Car pulls like a train on 12psi and about 80% injectors...turbo seemed to run out of puff at any more boost.

Cheers,

Troy

[Duk]

Bigger turbo!

[reecegze]

Has anyone got info on using the stock 4agze afm electrics ie which ones need to be used and which ones are axed also with the vac lines on the n/a inlet manifold