Felpro EFI review

Fri Jun 26 03:09:53 GMT 1998

here is some info on the Felpro unit
came from the Fordnatics list (forwarded with permission)

Clive 

>>Visited the URL, saw the car, bought the coffee mug.
>>Hey, did you notice the "sheetmetal intake manifold modified for
>>Fel-Pro's new port fuel injection system".
>>All I can say is huh? since when? anyone know anything more about
>>Fel-Pro's new PFIS?
>

This is a repost of a message I posted to the Buick mailing list a while
back. Hopefully it will help you in answering any of your questions
concerning the Felpro SEFI8LO. I have some experience with these systems on
the Ford's as well as I have helped out the Keen brothers some with their
unit. I also calibrated the Scranton brother's car for the Spring Break
Shootout earlier this year. If anyone has any specific questions or wants
further information, please feel free to email me.

>Hello list,
>
> Check out the
article in the May '98 issue of Chevy High Performance
>on the FP
Performance's new EFI system. It makes the Accel DFI look
>rather old. It
has 8 low inpedance injector drivers so you can taylor
>each injector pulse
width to meet your needs. It also has the ability to
>control the timing of
each individual cylinder independently of the
>other cylinders. It can use
a 5-wire wide band O2 sensor capable of
>accurate A/F ratios from 9.5:1 to
16:1! Check it out, it's pretty neat.
>

I have setup and programmed
several of these units on different vehicles
and I have to say that this is
the slickest unit I have ever seen. Not only
is it relatively simple to
calibrate compared to other units, it's also
very user friendly, very fast
and has some really trick features. One such
feature that is the slickest
thing I have ever seen is the ability to
record a run and the come back and
overlay it on top of your base fuel
table and play it back in slow motion.
This lets you analyze what happens
every step of the run and make changes
if necessary. It even has a
simulated engine sound that climbs in tone as
the RPMs go up! The closed
loop setup also makes calibration a snap. Just
plug in the A/F ratios you
want to use and the ECM will correct itself back
to the commanded A/F
ratios as long as your within the (user defined)
correction limits. This
way, you can play the run back, change the base
fuel map as needed and
eventualy remove the O2 and have a system that's
100% dialed in. The timing
table is also much more detailed than the DFI
and allows much more precise
control of the timing. It also has an
adjustment that allows you to set the
timing precisely and remove all the
guesswork from what your timing REALLY
is (Unlike the DFI).

While on the
surface, this unit may seem like a jazzed up DFI. Well, its
not. There is
SO much more going on here than meets the eye. This system
uses an entirely
different approach to delivering fuel to an engine than a
DFI. Instead of
setting up your fuel table according to base pulse width,
the Felpro system
works on a volumetric effiecient approach. There are
many, many factors
used to calculate fuel delivery instead of just plugging
in a base pulse
width and going like the DFI does. Engine size, injector
size, etc all play
an important role in the fuel delivery algorithm on the
Felpro system.
Let's say for example your car is running 55lb injectors and
the
calibration is perfect but you wanna switch to something different.
So..
you go out and buy a set of 83s and install them in the car and change
your
injector constant to 83lb/hr. Now.. while this won't get you DEAD on
the
money, it will get you very, very close so that only small adjustments
will
need to be made. Pretty slick, huh? This is a TRUE speed density
system..
not a lookup table system like the DFI has. Also, because the
system is
true speed density and uses the VE table, the smallest increment
of change
is 8 uS (microseconds), while the DFI is 64 uS. This is very
important for
cars running big injectors.

Another great feature of the system is the
aforementioned data logging
system. It allows recording of a "dashboard"
during a run. There are 15
"dashboards" that are preset but can be altered
by the user. You can pick
and chose between which ones you want to record
and also how many frames
per second you'll be recording. You can also set
the sensor that triggers
the recording process to start (Most every sensor
on the car can be used as
well as RPM, etc) and you can set where the
threshold is. Also, all data
recording is handled INSIDE the Felpro's PC
software (Calcom). You dont
have to exit the program and load the data file
into a text editor to read
it and analyze it. You also get nice graphs that
can be stepped through a
frame at a time as opposed to a big column on
numbers. However, the data
can be exported in a text file if you so desire.
The number of frames per
second can be adjusted from 1 to 50 frames per
second but is somewhat
dependent on the speed of the PC you're running
Calcom on. 50 frames on a
fast 486 is not a problem, tho. The limiting
factor is the number of
recordable frames per second which is right now at
150. However, with a 10
second car, that's still about 13 frames per
second.

Another great feature of the software is the editing ability to
cut and
paste, manipulate blocks of data and interprolate. You can cut
blocks of
data from an offline calibration and paste in into your existing
cal file,
change values in blocks of data without having to change EVERY
valve (like
DFI made you do) and you can even interprolate data by
highlighting four
corners of your map and telling the software to
interprolate between the 4.
Very slick.. similar to working with a
spreadsheet. Constructing a base
calibration is a snap. You can set every
valve in the VE table to 60-70 and
the car will most likely start and run
because the wideband O2 will bail
you out of trouble.

Sorry to be long
winded but hopefully this will help answer some of the
questions that
people have concerning this system.

Jay

Jay Carter
JCarter at Tampabay.RR.Com
10.92 @ 123 through the mufflers