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Discussion Starter · #1 ·
I'm plan to updatefollowing items: turbo (VF-30), injector (Sti) and fuel pump (255l/h).

I already have done these mods intake (CAI) and exhuast mod (TXS stealth back, Uppipe).

I'm running stock stock ECU now.
So, my question is can I put turbo, injector and fuel pump without
upgrading stock ECU to UTEC or UhiChip for a while (2-3 mo)?


Thanks for your help.

Taka
 

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Are you asking, is it safe? or OK performance-wise?

I would think performance will always be below peak or even decent whenever your engine management isn't tuned for your mods. Significantly so, as the mods increase.

As for safety, with a bigger turbo, unless you bring the boost way down, you'll definitely be running pretty lean (a lot more air w/o the ecu adding fuel). This would happen because during mild driving and aceleration, the O2 sensors are used and the ecu will "do the math" and add the necessary fuel, but during a hard acelleration, the a/f ratio will be a pre-determined map (originally set for the stock configuration). HAving better injectors and pump will allow a greater flow range with better capacity, but that alone does not add more fuel to the mix.

you should at least get a knock sensor, but I don't know of any members here you have no engine management and a big turbo. There maybe be some, but none comes to mind.
 

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Discussion Starter · #3 ·
I was asking for safety.

I don't have money right now to cover everything.
So I have to wait until i get enough money to buy UTEC or UniChip.


Thank you for your help
Taka
 

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The problem you will have is with the bigger injectors/fuel pump. You'll run VERY rich.

The stock ECU in closed loop (light throttle accelerations and cruising) will be fine. It will read the O2 sensor and adjust fueling to compensate for the larger injectors.

When the ECU goes into open loop (heavy acceleration I don't know the threshholds but over 50% TPS) you'll run VERY rich. In open loop mode, the ECU is not looking at the O2 sensor to determine fueling requirements. It's looking up static values from a table. Those values are based on the smaller injectors. So your big injectors will be dumping much more fuel.

Don't even bother putting the injectors in without some kind of engine management. I did my research and decided on the Utec. There is quite a waiting list so I haven't gotten mine yet, but I've only heard good things about them.
 

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I guess it's a matter of perspective. Cause pending on boost from the larger turbo, you run the risk of running real lean or rich, IMO.

I say, get a used unichip (<$500) to hold you over until you can decide/afford on the Utec. Or maybe an A/F controller. You can always re-sell.
 
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