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may avc-r is showin that my injectors are maxin out at 12psi but i see alot of carz running like 17psi on the standard injectors. any one know why that is. im running a rb25det turbo on a rb20det

Edited by cuong nguyen

As SK says... But you could replace your fuel filter and feed your fuel pump with better current capacity (larger) wiring and fit a rising rate FPR -Fuel press reg. and adj with some tuning on a dyno would be a good idea.

Are you still using the stock ECU? (well with a safc ofc you are :laugh:)

My injector duty cycle dropped almost 10% when I got a remap.

SK, 270bhp doesn't seem like alot... people get 150rwkw off the stock turbo and injectors, a few have even got close to 190rwkw off standard items.

I even got 150rwkw st 87% duty cycle. Raising the boost will increase fuel pressure and increase the max power you can obtain, correct?

if you dont have the cash for bigger injectors and your after some decent power using ur standard injectors all you have to get urself is a rising rate fuel reg there are different ratio rates available, so say u have std rb25 injectors (think they are around 380cc) and you plan on keeping them u use a rising rate 1:1.7 fuel reg so for every 1 psi boost you get 1.7 psi of fuel pressure,

so if you run 17psi of boost thats 28.9 psi of fuel pressure on top of your base fuel pressure which is probably around 30 psi which gives you a total of 58.9 fuel pressure which is quite high but this will make your injectors flow a fair bit more, since your pressure is now higher make sure all your fuel lines are in good condition or upgrade to higher quality hose

also make sure ur car is retuned after this,

hope this answers ur question cuong nguyen

Are you still using the stock ECU? (well with a safc ofc you are :()

My injector duty cycle dropped almost 10% when I got a remap.

SK, 270bhp doesn't seem like alot... people get 150rwkw off the stock turbo and injectors, a few have even got close to 190rwkw off standard items.

I even got 150rwkw st 87% duty cycle. Raising the boost will increase fuel pressure and increase the max power you can obtain, correct?

Happy dynos, or non standard fuel pressure.

270 bhp = 202 kw - 50 kw losses = 152 rwkw

The 270 cc's = 270 bhp rule assume 85% duty cycle

So 152 + 15% = 175 rwkw at 100% duty cycle

:woot: cheers :)

Happy dynos, or non standard fuel pressure.

270 bhp = 202 kw - 50 kw losses = 152 rwkw

The 270 cc's = 270 bhp rule assume 85% duty cycle

So 152 + 15% = 175 rwkw at 100% duty cycle

:( cheers :woot:

ya most people would have upgraded their fuel pump.

Raising the boost will increase fuel pressure and increase the max power you can obtain, correct?

Raising the boost will increase the fuel pressure, but it will also increase the manifold pressure on the open side of the injector by the same amount, therefore the pressure difference is constant over the injector. This is the whole reason for the fuel pressure regulator. It maintains an equal pressure across the injector so no matter what the manifold pressure, the same duty cycle of the injector will always give the same volume of fuel.

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