Bigger injectors on standard ECU?

[Flylux]

I found the following thread which is an interesting read. http://www.supras.com/~riemer/lexusriemer/lexusnotes.html

It talks about using the lexus v8 air flow meter on the Supra 7MGTE engine. The effect of this is for the engine to use more air without the computer realising it (until it detects the lean burn) without more fuel. They then use larger injectors which seems to allow more air and fuel without the computer believing anything is different to the standard setup. At least that is my interpretation of the article - someone please correct me if i've misunderstood!

What I want to know is...
Is this relevant to the 1UZFE ECU? Can it be tricked the same way?

Also there is talk of the 1uz engines from Crowns having smaller injectors than the Soarers. Is there any negative effect in swapping Crown injectors with Soarer ones while using the standard ECU?

 

[Lextreme II]

Your stock ECU will learn and re-adjust to larger injectors. Supposely the stock ECU can adjust up to 50% (please double check that for me someone). With Crown operates with smaller injectors, if you install the SC400 with 251 cc/mm, your Crown ECU will adjust the fuel mapping. I found out from my personally experience. This type of learn might takes weeks of driving.

 

[Flylux]

Lex,


In the forced induction tech forum you replied to Zuffen with the following.

Quote. The stock ECU is good until u upgrade to larger injectors.

And then in a later response - Stock injectors can handle 8 psi max. Therefore if you upgrade to larger injectors you will need to upgrade ECU. I would say over 350 cc/min. So 8 psi still valid.

Can you please clarify this for me. I know the other thread is also talking about fuel pressure but I am a little confused now.

Am I reading this out of context?

 

[Lextreme II]

When i say larger injectors, i mean beyond 350 cc/mn. Between 251 cc/mm to 350 cc/min the stock ecu should able to compensate. But it will take weeks to learn the new injectors. The ECU will try to lean it out with big injectors. I guess the final answer you are looking for would beyond 350 cc/min. You might have some rough idling with mid 300 cc/min injectors. Fuel pressure and all those thing would be another topic but i can answer some in here.

Stock Injector with Less than 8 psi : I would recommend a Raising Rate Fuel Pressure Regulator (RRFPR)

Injectors from 251-350 cc/min : Stock ECU should able to to re-learn the larger injectors

Beyond 350-440 cc/min : Depending what type of piggyback computer u will be using. I highly suggest one with fuel and timing adjustment.

I hope this will clear up some confusion. I am sure someone will jump in and correct if i am wrong.

 

[sideshow]

on a std engine u will not gain anything by fitting bigger injectors


i recently put an air fuel ratio meter up the tail pipe on my 1uz hilux

the mitures where perfect all over except for full throttle

some *** companies do this that when on full throttle it makes the mitures very rich like 10 to 1 air fuel

anyhting below 90% throttle the mitures were perfect
the only way u would gain power is by leanin the mixtures of at full throttle
when i get my air fuel i will do some tests

best thing to do it check mixtures first and see if u need more fuel
u will find that leanin mixtures of up hi will gain u hp