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Hi Guys

I Have got 740cc Injectors to go into my rb25 and i was wondering if there is anything that ill NEED to do other than fit them to make them work

Can i just Install them and drive away or is it a case of i need to do something else cause the ECU wont read them etc etc

They are actually Highflowed Injectors so technically there still stock just bigger holes....sort of.. LoL

Any help would be much appreciated if im on the right track of needed more than just to install

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https://www.sau.com.au/forums/topic/352142-rb25det-740cc-injector-upgrade/
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the injectors will foul and flood the engine of fuel unless you tune for the size.

speak to your tuner about it. You may also need a bigger fuel pump if the one you have isnt flowing enough.

Then the direct 12v of power, the other RB Guys should hep u with this

Edited by AaronNM35

Since you're doubling the size of the injector, you'll be injecting about double the amount of fuel - my guess is it wont even run that rich. With a programmable ECU you just use the injector resize function and it changes the signal it sends to the injector to compensate for the change. You then need to check and probably fine tune.

as people have said, with the stock ecu it can't be done. if you have an aftermarket ecu then it is easily done. fitting is a bit of a pain in the arse though. as for as what else you need, a new set of O-rings for the injectors is about it.

  • 2 months later...

Im currently trying to do the same upgrade, but im having trouble fitting them.

The problem i have is that the fuel rail i have (Greddy 11mm top feed) doesnt seem to fit with the standard intake plenum,

Does anyone know if there is a top feed fuel rail that will fit under the plenum with 700cc injectors? and if so, where can i get one?

Or is it not possible to fit a top feed fuel rail with the standard plenum :glare:

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