hazzaslim

I'm looking to buy some bigger injectors for my jdm impreza but I don't know what size is going to be the best for me. I have the walbro 255 fuel pump, hks induction kit, decat downpipe and boosting at 0.8 bar, keeping in mind that a remap will follow eventually.

JDM_Stig

iTrader: (3)

why do you think you need them ?

stonejedi

iTrader: (51)

Base injectors on your desired bhp total,but as above at a entry level it's not really worth it.Come to a decision of how much power you want to run and what modifications you want to make to your car and spec your injectors to that.SJ.

hazzaslim

bigger bang?

JDM_Stig

iTrader: (3)

Id love to hear this one explained fella.

hazzaslim

more fuel, more air bigger bang more power

silver6933

You seem to be running stock engine. In that case you do not need bigger injectors.

Injectors are scaled to be between 85-90% at max usage(fuel demand).

If you drop in injectors you will need a remap.

Get a remap done. If your injectors are exceeding 90% duty cycle then you need bigger injectors.

Note just putting in bigger injectors will make your already rich car run even richer and you WILL have less power.

You need only enough fuel to burn ALL the O2 in the chamber. And additional/enough to assist in cooling the chamber. Because each molecule of fuel cannot always find the free molecule of 02, we put in more fuel in the hope of burning all the o2.

Note you make max power when all the 02 is used in the combustion process. But is the ideal not the norm. Adding more fuel is not going to get you more power. too much fuel drops the chamber temps but egts go up iirc. Our cars are not OEM under specced in injectors.