Fuel Injector change for FE?

[gocamgo1]

Has anyone tried different injectors for better FE? If so, what types are there and and what are the gains? Do the 2002 civics have good atomization? Thanks,Cam.

[Angmaar]

I don't think changing your injectors will help with fuel efficiency.

[mwebb]

for maximum efficiency ;
it is very important that each cylinder receive the exact same amount of fuel as each cylinder should be receiving the exact same amount of air .

intake cleaning / decarb services , will remove deposits from the intake to ensure consistent flow as designed to each cylinder

you can send the injectors out to have them "bench" flow tested and cleaned so that each injector flows exactly the same amount as the others ,
"Linder tech" and "the Injector perfecter" are two reputable businesses that can provide this service

chevron techron and BG 44k in the fuel tank used with TOP TIER fuel will maximize cleanliness in your engine and fuel system between services

you can measure how well your engine flows with a vacuum gauge T eed into the Fuel pressure regulator line or the MAP sensor line on speed density systems , on Brake vacuum booster lines before the check valve on others .
in any event, higher intake vacuum shows a "cleaner" intake and lower intake vacuum shows a "dirty" system ,
a "good" intake vacuum value depends on the engine and altitude but at sea level "most" engines should be 20" or above at hot idle , an engine with very low vacuum may have additional problems .... if the engine has around 17 to 18" of vacuum , expect about 2" improvement after performing intake and injector cleaning
and expect a noticeable difference in overall drivability

other than that
best to not re invent the wheel .

[zonker]

Originally Posted by gocamgo1

Has anyone tried different injectors for better FE? If so, what types are there and and what are the gains? Do the 2002 civics have good atomization? Thanks,Cam.

i have changed out and tried different rated injectors on my mustang and found a slightly smaller than stock flow worked a little magic with the FE numbers.

BUT... the better way to go if you have the savvy is to get a tuner/programmer and readjust the injector pulse width per given load/rpm.

[tjts1]

If you have pintle type injectors (2002 civic does not) its a good idea to look for disk type injector of similar flow rate.

http://www.youtube.com/watch?v=NIz5c...eature=related

http://www.youtube.com/watch?v=Emnax2J4FX4

[mwebb]

..."BUT... the better way to go if you have the savvy is to get a tuner/programmer and readjust the injector pulse width per given load/rpm."...
on the surface it may seem like this is true ...
it is not really true at all.
if you change base injector pulse width , Mr ECM will see the results in the 02 sensor or AFR sensor and simply adjust injector pulse width back to maintain the Air Fuel Ratio right where Mr ECM wants it to be .
( usually but not always at 14.7 to 1 )
this change in IPW will be reflected at first in short term fuel trim , then after a short while in Long term fuel trim which will allow STFT to revert to bouncing a few percent up and down from zero fuel trim adjustment

despite what you may have read;
you can not fool Mr ECM , if you try Mr ECM will punish you and your engine

[Piwoslaw]

So, just reducing the amount of fuel going through the injectors won't work for certain cars, unless it is paired with hacking the signals from a few sensors, I guess.

But what if the injectors are swapped for something with similar flow, but with better atomization (which is what the thread's starter had in mind, I believe)? Let's say that my engine has 5-point injectors, while a new version of that engine has 6-point injectors. Would my FE benefit from the upgrade? Would I also have to swap the ECU?

[zonker]

there are tuners that do not get un-learned thru the ecu, and they involve remapping your ecu - like a moates 1/4 horse for example.

also, if your car is pre obd2, you can cut the 12v constant and tap it into a 12v switched line so the ecu resets on every start up.

the reason i say not to do it on obd2 is because smog checks that tap into the cars ecu will see that not enough parameters have been learned and the smog check will fail. obd1 however does not have this problem.

[tjts1]

Originally Posted by Piwoslaw

So, just reducing the amount of fuel going through the injectors won't work for certain cars, unless it is paired with hacking the signals from a few sensors, I guess.

But what if the injectors are swapped for something with similar flow, but with better atomization (which is what the thread's starter had in mind, I believe)? Let's say that my engine has 5-point injectors, while a new version of that engine has 6-point injectors. Would my FE benefit from the upgrade? Would I also have to swap the ECU?

It might benefit but I doubt its worth the effort. The big benefit is going from the old EV1 single pintle injectors to any type of disk injectors with 4 or more holes. I converted 2 old cars from pintle to 4 hole disk injectors of the same flow rate. The both run great and passed emissions tests although I can't quantify if the newer injectors improved FE. I would love to get my hands on EV14 injectors although they are few and far between in the JYs.



EV1 left and EV6 right


Ev14 nozzle

[pana]

I currently have a set of these upgraded 4-hole Bosch injectors for my HF but I don't drive enough to get good FE improvement readings. I do notice easier starts and smoother acceleration. I have 1 free set available for someone on this forum willing to install these and keep a log on FE improvements (if any) and then post up detailed results. This injector set will drop right into any 92-95 VX, CX or HF engine. If you have an 88-91 HF I will include the resistor box delete plug. Please PM me if interested.