Fuel Injectors

[fadz]

hi just a question , iv been told bigger fuel Injectors, increase performance in a certain way... i have a 94 model vti civic
can anyone answer this and let me know if its worth doing, thanks cyaz!!

[BLKCRX]

That is 100000% absolutely completely wrong. Correct tuning produces more power with certain about of fuel and ignition, this can only be done via EFI devices, simply adding more fuel will almost most certainly decrease your performance and fuel economy.

[fadz]

i jus thought bigger injectors means mor fuel goes in...and wen fuel burns quicker...car wil get bit mor speed... anyways thnx for answering my question

[BLKCRX]

Not if there isn’t enough combustion for the fuel, or enough spark, everything has to be in correct and optimal doses for gains, if not you will lose power.

[ProECU]

i jus thought bigger injectors means mor fuel goes in...and wen fuel burns quicker...car wil get bit mor speed... anyways thnx for answering my question

you need oxygen to make fuel combust.

pick up a chemistry book if you want to learn more, its all in there

[Boost]

whats the approx. pulse width of each injector firing? im thinking its somewhere between 3ms - 10ms.. but can seem to narrow it down to an exact value..

[ProECU]

i'll look at some datalogs and post some data for ya

pw will typically increase along manifold pressure & rpm until peak torque and then either remain constant or decline (depending on tuning) after peak torque.

[Civic Type R]

i jus thought bigger injectors means mor fuel goes in...and wen fuel burns quicker...car wil get bit mor speed... anyways thnx for answering my question

Thats the same ideology as chopping your springs to lower your car.

[wynode]

i'll look at some datalogs and post some data for ya

pw will typically increase along manifold pressure & rpm until peak torque and then either remain constant or decline (depending on tuning) after peak torque.

So basically the duty cylce varies depending on load and rpm..... ?

[ProECU]

yes... and peak torque and volumetric efficiency

[Boost]

Cool can you post up some data ProECU for some typical injectors and high flow ones...
im thinking PW is proportional to the manifold pressure ( volume of air going in) so that you get the correct AFR and the injector frequency is proportional to rpm, so that the number of times the injector is fired is fired once every 2 rpms. hmmm

[ProECU]

RC 550cc injectors, stock fuel pressure reg.
ive even graphed the data for you guys.

this is live data from a WOT run of one of my customers cars.
(right click and save-as)

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