I'm going to try and edjucate New EFI owners a bit here,,
Hopefully the data will be understandable.
I will add general info as I go..as best I can.
Some of this stuff Is very complex and way more than most of us
need to know. I'll try and leave that out.

Lets start with a Fuel tuner Comparison chart, I will not list them all,,
just the most popular.

XieD
Type: 02 offset
Application: Mild, Free flow air breather and Baffled pipes only
Ignition timming: No
Idle and cruise: Yes
Accelerate and top end: No
Tunable: No, Non adjustable so a dyno Is useless.

V&H FuelPak
Type: Indirect
Application: Mild
Ignition timming:No
Idle and cruise: Yes
Accelerate and top end: Yes
Throttle Bands: No
RPM resolution: No
Tuneable: No,,uses V&H tables only, these are limited and the
manufacturer does not provide the Information needed to effectivly
adjust the product on a dyno.

Power Commander V
(I will skip pc3)
Type: Map
Application: Any (Stage two capable)
Ignition timming: Yes
Individual cylinder: Yes (tuning for each cylinder seperatly)
Idle and cruise: Yes
Accelerate and top end: Yes
Throttle Bands: 10
RPM resolution: 250,500
Tuneable: Yes,,takes about an hour for a "Skilled" dyno man to tune both cylinders
over the full range of RPM and throttle openings on a dyno equipped with dual AFR sensors.

ECM programmers, the Sert, stage one download from HD
All spec's same as PCV BUT takes about three hours dyno time to
get It spot on,,Now you know why HD serts don't always work.
They set them about right hopefully with a dyno run,
They know paying for three hours of dyno time will **** people off,,
and there Is no need anyway because they must stick to the EPA compliant AFR
So a quick check of the fuel tables and AFR is all you get just to make shure there
are not flat spots that could cause you problems.

Zippers Thundermax
Type: Map auto tune
Application: Any (Stage two capable)
Ignition timming: Yes
Individual cylinder: Yes (tuning for each cylinder seperatly)
Idle and cruise: Yes
Accelerate and top end: Yes
Throttle Bands: 55
RPM resolution: 256
Tuneable: Auto tune equipped BUT a dyno Is the safest way to tune
for maximum throttle openings and RPM

Master Tune was not Included In the research. From what I've seen
It compairs very closely to the PCV.

NOTE :
"Throttle bands" numbers like 250 or 500 means user selectable RPM bands.
Basically check points for the dyno man 250/500 means 500-RPM bands above 3000
Using the widest effective band reduces dyno tuning time.

 

When deciding on a tuning product look past the fancy names
and sales claims because they don't Impress your bike.

All It wants Is the right amount of fuel added to the amount of air you give It when you twist the trottle.

 

I'll tackle open and closed loop next,,gotta go ride,,,

 

This system Is very complex, too much so for me to try and explain with
my Limited knowledge and the data/info I have before me.
So I will list a few facts and conditions of operation.
This will hopefully dispell a few myths.

The Basics:
02 equipped sportsters amd Twin cams run In two distinct modes, closed
loop on the sensors at Idle and cruise, and open loop on the fuel tables
or maps on acceleration and at top end.
If you can live with normal, your bike's engine can to. And with synthetic
Oil the engine won't go lean enough to hurt It self.

02 Off-setters, "Xied's" reset the AFR to 13.8 or 14.0 work ONLY In
closed loop mode which means they cannot help an off-Idle lean stumble
or work at top end. But most of our riding Is done at Idle or cruise where
they WILL work.
Still since they use the stock, closed loop system, we're stuck with one
AFR from light to 3/4 throttle. However 14.2 or 14.0 Is definitly better
than 14.7. Below 13.7 mileage may drop and your working over the
electronic edge of Narrowband sensors.

Wideband 02's are for Auto tune systems only so don't think you can
swap those out, they need an electronic Interface box.

Our system uses Intake and head temprature along with the 02's taking
samples of the oxygen level In the exhaust gasses.

Narrowband 02's Do Not help adjust the bike for altitude and weather.
This system's only purpose Is to control emissions by hunting for that
good old 14.7 stoichiometric AFR that yeilds the most complete
combustion for minimum emissions.

When It gets colder out side the Air density Increases and the system
does not compensate for that and the bike runs a bit leaner still.

My EFI bike loves the heat, 92 degree's, sun cookin the asphalt,
My bike want's to please me real bad.

 

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