so i was thinking of ways to increase fuel in obd2 cars that are not chippable.

first off. im well aware of the options for tuning so please dont troll about them...

i want to keep the obd2 port functional with stock ecu and immobilizer.

so i was thinking what would be other ways to change fueling.

so i came up with few

finding the injectors with exact fuel curve that you need to replace stock injectors.

bumping the fuel pressure up with a reasonable tradeoff in closed loop fuel trim


and then last thing.

making a simple rpm based circuit with a programmable chip( adruino for example)
that increases the voltage to fuel pump as rpms go up. with a chip it can be programmed to be exact throughout the rpm range in open loop and act as a normal fuel pump in closed loop below certain rpm

please dont flame or post stupid replies im just sharing some ideas and want some feedback from people that know what they are talking about

 

Adjust fuel pressure, and then change the pump as needed. This is the simplest way to add fuel to a stock engine. The increase in fuel will be detected by the ECM, which will reduce injector pulse width, until the point where emissions prevent it from reducing fuel any further. Once you hit system too lean, you can no longer increase fuel this way.

Pulse-width modulating the fuel pump is used in a lot of return-less fuel systems. It's benefits in a technician's view are not worth the complexity of diagnosis and implementation. Sometimes making the wheel more round is fruitless.

 

has anyone used these fuel systems on honda?
http://fuelab.com/products/performan...ure_regulator/

its an electronic fuel pump/fpr system that supposedly gives you linear fuel pressure unlike mechanical FPR slope.

what i meant is something similar to this system where one could program a specific slope to compensate for engine changes.
for example

if i increase stock pressure the stock fuel pump and fpr will change the slope also changine the low rpm operation which would mean ecu would have to adjust more trim

if i could program a specific fuel pressure output per rpm i could make mimic a stock fuel pump until the ecu goes into open loop at wot
or maybe fuel pressure based on map sensor and rpm

it seems to me that this system( fpr, fuel pump and restrictor) can control the fuel delivery with enough precision to do that


this is a theory so everyone chill out i dont care if its too complicated its a discussion

this is to keep a modified obd2 car emissions friendly and have the stock ecu and obd2 port.

pretty much use the fuel system as a control for fueling and let the ecu do the fine tuning after it

if you ask why then ask why vafc was created. again this is just a theory please keep your shitty comments to yourself if you dont want to discuss it then move on

 

This is a shitty thread when there are tons of support out in the market already at an affordable price.

 

enlighten me what is there for fuel tuning for obd2 ecu besides a piggiback like vafc?
since you keep posting garbage in my threads yet when i ask you a question you dont say ****

 

Why do i need to answer your question when you answer your own question. If you can't pay to play, then you shouldn't even be modifying your car. Vafc and Safc are good cheap fuel tuning device.

 

because read the damn post if you have nothing to add then go ********** in your closet and go troll in gdd

 

Who would care about that idea, Vafc and Safc is what your wanting.

 

if i wanted them i would already get them bro. again with your bullshit replies

 

Then go get an AFC and quit making pointless threads

 

troll u have nothing to add dont post

 

But he's right......






No matter how you inject fuel,the PCM wiil see the mixture and attempt to compensate.


Whats the point anyway? Power on most vehicles is achieved at about 13:1-13:5 and fuel economy comes from using as little fuel as possible before running too lean......

 

if I upgrade few things and car starts running lean at high rpm.

the electronic fuel pump would allow me to increase fuel only towards the top end and not the low end or midrange
ecu runs off the maps at wot

if I increase fuel pressure with stock fpr it will increase everywhere and make the ecu throw a code for too much fuel compensation like it did with 40 psi at idle on stock p2t ecu

but I could use some more fuel in vtec and top end

the pump I posted a link to has a linear output

it was running close to 16 afr with stock maps in vtec and at wot

 

There is a problem and it has nothing to do with the additional added aftermarket parts. You need to troubleshoot why the vehicle is leaning out at hevaier loads.....(if this is your car)






*You should also be aware that fuel pressure will never be linear in a fuel injected vehicle. Thats is why the specification is somewhat wide.*