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Denso 550cc Injectors And Stock 270 Cc Injectors

DFAULT

By DFAULT,
in Engines & Forced Induction

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DFAULT Mentor

DFAULT

Posted
Posted

Hey

need help

Rb20det

i've just brought some 550 cc injectors and a remaped ecu for the 550 cc injectors

turbo etc...

my power goal is about 220-230 rwkw

The remap ecu is for the 550cc injectors BUT if i use my stock 270cc injectors will that be ok

cause i know there good for about 240 rwkw max

or is it the remap ecu can only be used with the 550cc injetors

Will it stuff up using the stock injectors with the remap for 550cc injectors

Thanks for your time

Really appreciate the help

letemlaf Rising Star

letemlaf

Posted
Posted
If you run the new fuel map made for the 550cc injector with your factory 270cc it will run extremely lean; I would not recommend doing so.

A similar question again...

If you run a fuel map for smaller injectors than the ones currently installed (eg installed bigger injectors but not yet tuned) is there any ill effects doing that?

Mr. Oizo Grand Master

Mr. Oizo

Posted
Posted
A similar question again...

If you run a fuel map for smaller injectors than the ones currently installed (eg installed bigger injectors but not yet tuned) is there any ill effects doing that?

will run very rich

kudos.motorsports Grand Master

kudos.motorsports

Posted
Posted

Think of a fuel map as simply an automated tap, and the injector the hose. Under the same pressure (fuel pressure) a smaller hose will deliver less liquid than a larger one. The fuel maps are preset timers for injectors under certain conditions (airflow, revs etc) to open for a period of time.

Therefore the exchange for smaller injectors, under the same pressure, will allow less fuel through in the same given time frame while larger items will deliver more fuel at the same pressure.

*Fuel and ignition although preset do have modifiers such as water temp, air temp, o2 reading etc however these are only to optimized the fuel mixture not compensate for the excess/lack of fuel from injector upgrades.

Mr. Oizo Grand Master

Mr. Oizo

Posted
Posted

If you already have the 550cc injectors, and the ECU for the 550cc injectors, why do you want to use the 270s?

I highly doubt they will make it to 240, probably around 190 if you bump up the fuel pressure

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