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Discussion Starter #1
im having an issue with my car being rich under WOT im hitting around 9.2-9.5 AFR when i do a pull. i was reading that was too rich and im not seeing the power i should be. car has a NAT gte ecu mod basically running a stock supra set up. Could anyone help me, what are the main senors that control AFRs at WOT, what should i check. AFRs are fine when cruising and idle. could it be the FPR im still on the stock one?

replaced
TPS sensor
O2 sensor
Gm Iat
 

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From the land down under
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Have you popped off the cover of your ECU to check the condition of the capacitors inside? These are getting pretty old now, and plenty are having issues.

Mine used to do the same under certain WOT conditions, and it had leaky caps.
 

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Discussion Starter #3
I had my ecu caps replaced by drift motion. Lucky caught it before major leaks. I may have fixed it, put new plugs new and ordered oem VVTI coil packs. Was thinking my engine wasn’t using all the fuel and was blowing it out from bad spark. My plugs got washed and cheap ass coil packs.
 

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You weren't very specific. 'Stock Supra setup' can mean a lot of different things.

Exactly which ECU do you have?
Exactly which injectors are you running?
How much boost are you currently running, and what's your turbo setup?
Which MAP sensor and O2 sensor are you running?
Do you have an adjustable fuel pressure regulator (AFPR), and if so, what's your base pressure set to?

The injectors available to use in a GE top feed rail will never exactly match the behavior of the stock 2JZGTE side feed injectors. I believe the injectors you're running, even if advertised to match the GTE ECU you've got installed (JDM 2JZ-GTE w/440's, USDM 2JZ-GTE with 550's, etc) are flowing more than the side feed equivalent. This is fairly common and is the result of different injector nozzle configurations and injector behavior, dwell time, etc when driven by the stock ECU.

I would recommend adding a simple piggyback 'fuel controller' like an Apexi S-AFC, and adjusting that using your wideband feedback to get to the 10.5:1 or 11.0:1 ish you should want to see. Obviously, this only works within the limitations of your stock ECU and pump premium fuel.
If you don't want to fuss with an SAFC, I would recommend an AFPR and reducing your base pressure a little bit at a time until it's your desired A/F ratio at WOT.
 

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Discussion Starter #5
Aristo Jdm ecu
Osidetiger 440cc injectors
Running 8psi
Cx racing gt35 turbo
2jz oem map with Denso 4 wire o2 sensor
Stock fpr

ok thanks for the head up on the info about the injectors I didn’t know that. After I put in the oem coil packs. that was the next thing on my list was to get a adjustable FPR. Would lowing the fuel pressure be safe. Does that effect normal driving AFRs.
 
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