rb25 injector?...

[fly240]

Hi, I wonder if any one can verify me what's the maximum horsepower rb25det injector can hold?.....thanks.

[Darius]

I bet one injector could support 50 hp?

[Joe]

basically when you upgrade the turbo, you need injectors.

[fly240]

yes, i'm doing a t3/t4. Will the bigger injector do any good with out tuning it. let say just take the stock out the drop in the bigger in, will it help?..

[themadscientist]

Without tuning the bigger injector is going to be tasked at the same duty as the smaller one was washing down your cylinders.do it right or don't do it.

[Joe]

yes, i'm doing a t3/t4. Will the bigger injector do any good with out tuning it. let say just take the stock out the drop in the bigger in, will it help?..

you cant drop in injectors without tuning.

[Carl H]

sure you can, you'll just hydro lock the motor when it goes to 100% duty...

[fly240]

so all saying with out tuning, you can drop it in but the performance will be the same as the stock injector.

[Joe]

no.

you cannot put a bigger injector in without a tune.

the computer knows how big its injectors are, and based off of airflow it knows how much fuel to add so you have a proper mixture. it has fine tuning adjustments over this but NOT enough for an injector upgrade. since your injectors will be significantly bigger you will basically flood your engine with gas because it keeps them open too long.

YOU MUST TUNE IT. PERIOD.

[mello88]

no.

you cannot put a bigger injector in without a tune.

YOU MUST TUNE IT. PERIOD.

Yeah you have to either ROM tune your ECU, or step up to a programmable ECU, or do a janky solution like a S-AFC. Otherwise, like everyone is telling you, it will NOT work.

To answer your original question regarding the amount of horsepower each injector can support... On a six cylinder engine with six injectors, you can estimate the maximum supportable crank horsepower as the CC rating of one of the injectors... So like on the RB20, the stock 270cc injectors can support up to 270hp at the crank at 100% duty cycle [in a perfect world]. In reality you want to stay under about 80% duty cycle, so take your stock inj rating, 370cc, and multiply by .80 duty cycle to get a "safe" max power rating of up to 296hp at the crank.

Get some 550cc to 720cc injectors, a ROM tune or a PowerFC and you're good with the t3/t4 on RB25
Modified by mello88 at 1:19 PM 8/6/2007

[fly240]

thanks, any one knows where i can get a ROM TUNE...will jim wolf technology do it.....?

[fly240]

has any body use Greddy E-manage before..?how about hks fcd...?
Modified by fly240 at 2:25 AM 8/8/2007

[fly240]

has any body try to use the new Apexi SAFC NEO yet.....and how was it..? any suggestion on this fc...?

[craz4240]

Talk to Carl H and bring cash.