Injector question

[macx]

Going to ohm my injectors, about 80k miles.

There's a possibility one or more of them aren't functioning quite right.

If I find I need one or more replacements, I've read that using the next
size larger injector (15 lb/hr versus the stock 14 lb/hr) can help power
in the mid and esp upper rpm ranges (just talking moderate street rpms
with a stock engine). That would be nice to have a little more torque
for pulling my bike trailer up hills on the highway. Not interested in
making big changes like going to 19's or anything, bigger cams/throttle
bodies, head work, etc. Am going to an electric fan, tho, as I've had
great success doing that on a couple other vehicles, altho with moderately
warmed up 5.8 small blocks. Better economy by about 1-1/2 mpg
the main improvement. I've got a spare small e fan I replaced with a
larger one on one of those rigs, and that spare would work great in the
Ranger. With only 100 hp stock, removing parasitic drag of even 3 to 5
hp couldn't hurt. Anyway, back to the injectors -

The article I read said to enlarge the hole in the mass air by a similar
% of cross section area - I've got experience with 5.0's and efi EEC-IV
.8's that have been modified, including larger mass air/injectors etc.

I'm not so sure about drilling out the mass air here. The 15 lb injectors
are only 7% larger flow than stock. One thing I do plan is to take a look
at the intake tube silencer and maybe remove it to allow more airflow.
Might that be enuf for just slightly larger injectors?

I know in 5.0's the stock computer will adapt and learn within a reasonable limit.
And that messing with the mass air airflow can mess it up and cause turbulence
which makes it worse instead of better.

Any experiences?

 

[scotts90ranger]

Swapping to larger injectors isn't going to get you squat unless you massage the cylinder head (assuming you have a 2.3 since you mention 100hp). The stock injectors were sized to the engine plus a reasonable safety margin. If you put larger injectors in the computer will just pull the extra fuel out anyway. The stock fueling strategy should be set up to have an optimal air fuel ratio up until about 3000rpm when the exhaust starts getting hot, being gasoline if you add fuel it cools the exhaust so it will start richening the mixture. If the exhaust gets too hot the valves can tulip and/or the pistons can get burnt. Peak power is achieved at around 12.5:1 air fuel ratio (normal below the power enrichment is 14.7:1) which the engine most likely gets near at full throttle high load. If the stock injectors are able to get there then they are good enough.

I think I know the website you are thinking about, as it's been pointed out before but most of the data is BS as it's just someone thinking things without knowing the theory behind it...

Removing the air muffler might get you a little, will just make it a little louder

 

[macx]

Yeah, I had started thinking that about that web site.

Like I said, I've had a fair amount of experience with this same basic EEC-IV
mass air system on 5.0's and a warmed up 5.8 using an "enhanced" 5.0 system.

I've often wondered about the Turbo setups for the 2.3, sounds like a neat little
package.

But I bought a 2.3 purposely for economy driving the 80+ miles a day for work, so
am trying to resist doing anything other than making it run as good as the basic stock
design can run.

If I wanted a hot rod, I'd slide in my moderately hot rodded 5.8 Lightning engine and
beefed 4R70W . I was amazed, but get 21 mpg on 87 in a 4,000+ lb car with 3.55 gears
with that engine. I'm sure it's becaue all the major components (heads, intake, cam)
are well matched, along with a well set up efi system.

In a Ranger weighing 25% less, I'd probly get about the same mileage as with the 2.3.
But where would I get any traction!?

 

[feellnfroggy]

I don't see where running the 15's would hurtu any. Might as well I've it a shot. As far as the maf don't mess with it. Remove the silencer and maybe even use an open element filter in thefenderwell. But for pulling your bike, gears are the best option.