SIISFLY

I'm using a Field VTEC/fuel controller to do the tuning.

When I add fuel, say 5% over stock, it reads out OF, meaning the injectors have maxed out. Of course, this only at WOT. Cruising, no OF readings from the Field.

What I'd like to know is, when this happens, is it the injectors that are maxed out, or is it the amount of fuel flowing that's insufficient to be able to bump up the fuel 5%?

I've bumped up the fuel only after 5000 rpms to 5% up to 8000 rpms. I know this is ghetto tuning, but I'd like to address this issue before I get a chance to hook up a wideband and tune it that way. In the case I need to add fuel anywhere, I won't be able to.

This is with stock ECU, boltons, and a CTR intake cam. With only these mods, are the stock injectors already running near full cycle??

snatch

Which engine is this on?

I thought I read somewhere a few days ago that Civic injectors are good until ~200hp.

IHateJDM

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ****** &raquo;</TD></TR><TR><TD CLASS="quote">Which engine is this on?

I thought I read somewhere a few days ago that Civic injectors are good until ~200hp.</TD></TR></TABLE>

i've heard 250.

BLUE EH3

get a aem fpr

SIISFLY

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ****** &raquo;</TD></TR><TR><TD CLASS="quote">Which engine is this on?

I thought I read somewhere a few days ago that Civic injectors are good until ~200hp.</TD></TR></TABLE>

I have a b16a. I guess I should just get a A/F reading.

IHateJDM

wideband o2 is the only way to know for sure.

snatch

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by IHateJDM &raquo;</TD></TR><TR><TD CLASS="quote">wideband o2 is the only way to know for sure.</TD></TR></TABLE>

This is true. Don't bother with the Autometer Narrowband light show.

SIISFLY

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ****** &raquo;</TD></TR><TR><TD CLASS="quote">This is true. Don't bother with the Autometer Narrowband light show.</TD></TR></TABLE>

That's for sure. It's purty to look at though.

Would you guys recommend getting a wideband controller and getting the readings myself, or having this done on a dyno?

Padawan

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SIISFLY &raquo;</TD></TR><TR><TD CLASS="quote">That's for sure. It's purty to look at though.

Would you guys recommend getting a wideband controller and getting the readings myself, or having this done on a dyno?</TD></TR></TABLE>

I always suggest dyno tuning (with a wideband O2). Simply tuning by A/F ratio will get you decent and safe results if you do it properly, but won't necessarily give you the largest or smoothest power curve. Sometimes what looks "ideal" from a pure A/F standpoint isn't what the motor prefers for making the best power. By tuning on a dyno with a wideband, you can tune for power while keeping the A/F ratios at safe levels.

SIISFLY

Good point Padawan. I'm just worried in the event that more fuel becomes necessary in the higher RPM range to get that ideal power curve, that the fuel cannot be added due to the Field unit saying the fuel injection is maxed out. Has anyone with a VAFC or Field had the same experience, ie. you wanted to add fuel but couldn't? Did the addition of a FPR resolve the problem?

I just want to get the motor tuned as best I can for now. I think I'll be happy with the mods I have for now, until I decide to up the compression and maybe upgrade the valvetrain.

Padawan

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SIISFLY &raquo;</TD></TR><TR><TD CLASS="quote">Good point Padawan. I'm just worried in the event that more fuel becomes necessary in the higher RPM range to get that ideal power curve, that the fuel cannot be added due to the Field unit saying the fuel injection is maxed out. Has anyone with a VAFC or Field had the same experience, ie. you wanted to add fuel but couldn't? Did the addition of a FPR resolve the problem?

I just want to get the motor tuned as best I can for now. I think I'll be happy with the mods I have for now, until I decide to up the compression and maybe upgrade the valvetrain.</TD></TR></TABLE>

An adjustable FPR is definitely a good idea if you'll be tuning with the Field. Adding fuel with a Field or V-AFC alone isn't always effective, especially in the upper RPM ranges, due to the way in which the units function.

Basically, these units add or subtract fuel by intercepting and altering the signal from the MAP sensor before sending it to the ECU. If you're trying to subtract fuel, the Field will take the true MAP signal and reduce it, making the ECU think less air is entering the motor, and thus causing the ECU to provide less fuel.

Conversely, if you are trying to add fuel, the Field tries to "fool" the ECU by increasing the MAP signal. The problem here is that, at WOT in the higher RPM ranges, the MAP signal is often already approaching its upper limit. The Field is therefore unable to add any significant amounts of additional fuel by boosting the MAP signal further, and in many cases a CEL is also triggered.

Generally, when attempting to tune with such a device, a tuner will make a "base-line" run to determine what areas of the curve need more fuel, and will then increase fuel pressure (via an adjustable FPR) until all of the lean spots have been taken out. Then, he will use the Field to remove fuel in areas that are too rich until he achieves the A/F curve and power band that he's looking for.

SIISFLY

Excellent info! Why I didn't realize the Field achieves its "tuning" ability by using the MAP signal is... well dumb. I should've known. That puts it all in perspective. Thanks!

FPR here I come.

Now, has anyone messed with MAP sensor to achieve a wide fuel adjustment range, or is this just not a route to take?

IHateJDM

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SIISFLY &raquo;</TD></TR><TR><TD CLASS="quote">Now, has anyone messed with MAP sensor to achieve a wide fuel adjustment range, or is this just not a route to take?</TD></TR></TABLE>

Sensors just send a voltage back to the ecu based on their reading. The ecu is what determines what range the voltage should be in. If it is a reading that is not in range, it throws a cel. I'm sure you could desolder/replace parts on the ecu board to adjust the range, but it really isn't a good idea.

SIISFLY

I see. Yeah, I don't think I'd trust myself messing with the ECU itself. I wouldn't even know where to begin.

Are there any issues with increasing the fuel pressure w/ the stock injectors, ie. shorter life expectancy of the injectors, etc?

Thanks for everyone's input!

IHateJDM

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SIISFLY &raquo;</TD></TR><TR><TD CLASS="quote">Are there any issues with increasing the fuel pressure w/ the stock injectors, ie. shorter life expectancy of the injectors, etc?
</TD></TR></TABLE>

Not that I know of.

Padawan

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SIISFLY &raquo;</TD></TR><TR><TD CLASS="quote">Are there any issues with increasing the fuel pressure w/ the stock injectors, ie. shorter life expectancy of the injectors, etc?</TD></TR></TABLE>

At excessively high pressures, the pump can become overworked, and injector spray pattern and metering can possibly be compromised to some degree. However, if you keep the pressure reasonable, you shouldn't have any problems.

SIISFLY

Cool. I shouldn't have any problems then. I doubt I'll need too much more fuel just for boltons and a type r cam. Damn, this makes me wanna upgrade the valvetrain while I'm at it!!

sohcvtec1995

Yea just get a pump, injectors, and a FPR.

timisyourfriend

Just FPR... other 2 will hold up no problem as long as they are in good working condition...

IHateJDM

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JZPerformance &raquo;</TD></TR><TR><TD CLASS="quote">Just FPR... other 2 will hold up no problem as long as they are in good working condition...</TD></TR></TABLE>

x2

SIISFLY

I'm looking at the B&M FPR. I don't think I've heard horror stories about this one so I think I should be good. I know the AEM's been around for a while, but I just hate the fact I have to cut the stock one and mickey mouse it to make it adjustable.

Padawan

The B&M unit will work fine. You can usually find the FPR and gauge as a package for quite a good price. Modifying the stock piece to install the B&M is not difficult - just take your time and follow the instructions, and you won't have any problems.