"Technology for Tuners" Newsletter #1
This is Innovate Motorsports' "Technology for Tuners" Newsletter,
Issue #1. These updates are intended
to keep you informed of LM-1 tuning tips, firmware
updates, application notes, new product releases,
company news, and other useful information. In
this issue:
1) RPM-Converter Input Cable update
2) Visit us at SEMA 2003- Booth #12469
3) LM-1 shipments set new record in September
4) High-temperature applications update
5) Tuning Tip: Issues with Air Pumps
RPM-Converter Input Cable update
The first two of our three planned auxiliary input cables are now
released from engineering. Aux. cable #1 is a simple break-out cable
that extends the mini-DIN 7 cable to a set of screw connectors. But
the big news is the Aux. cable #2- the RPM converter cable. This cable
can take a signal from an inductive clamp OR the tach output from
your ECU/ignition system, and convert it to an analog signal that
is “log-able” by the LM-1. The cable can be calibrated
to the characteristics of your engine (# of pulses per crank rotation)
through a simple setup routine. And you still have 4 screw terminals
left for connecting other inputs. We are field testing, taking back
orders, and plan on shipping in the next few weeks.
Visit us at SEMA 2003- Booth #12469
If you’re planning on attending SEMA 2003, drop by booth
#12469 and say hello to the Innovate
team. Klaus, Cort, Patrick, James, and Robb
will be there answering questions, handing out information,
signing up new dealers, and drinking too much
beer. We’ll
be raffling off one LM-1 per day, so send your
friends over, too.
LM-1 shipments set new record in September
LM-1 sales and shipments hit a new record in September. We can safely
say that this is a popular product. We’re doing our best to
provide solid support, and bring out quality accessories over the
coming months. To all of you who purchased an LM-1 in September- thanks!
High-temperature applications update
The Bosch LSU4.2 wide-band O2 sensor (shipped as part of the LM-1
kit) is rated to operate at an exhaust gas temperature
of < 1300
degrees (F), and a sensor housing temperature
of < 900 degrees
(measured at the bung) for maximum accuracy and
control. When either of these operating temperature
ranges is exceeded, the sensor can
no longer be accurately controlled. Further,
operating at or over these temperatures for any
length of time can significantly reduce the lifetime
of the sensor. The LM-1 is designed
to display an error message under these conditions
(currently 08- Sensor Timing
Error) rather than provide inaccurate readings.
For some turbo vehicles, rotary engines, and
other setups, this error message can be encountered
with annoying frequency. Some tips to avoiding
the sensor timing error:
1) Move your sensor bung as far downstream
as possible. Right before the cat, or 2-3 feet
from the end of the tailpipe
are good locations. 6” from the turbo is generally not an
optimal location.
2) Some users have had great luck with a self-fabricated
simple heat-sink fin. This works because it
assists in cooling the sensor body. Take a 4-5” square piece of copper (optimal) or
aluminum, and punch/drill a hole just big enough to fit over the threads
of the O2 sensor. Bend it so that there are two “wings on
either side of the sensor. Mount the heat fin between the sensor
and the
sensor washer.
Tuning Tip: Issues with Air Pumps
Many vehicles (Mazda RX7s, for example) have a pump that pumps
air directly into the header behind the ports
or valves during warm up and then switches to
pumping air into the cat after the cat is hot
enough. We have seen numerous cases where the
switching valve was completely or partially stuck and air
entered into the headers even after it
should have been switched off. This will of
course make the AFR read lean because of the
way WBO2 sensors work. Try to disconnect the
air pump and then read AFR.
If your air-pump setup is as described, there’s a good chance
that your exhaust is in reality very rich, but
reading lean during the first 10-15 minutes of
operation because air is being mixed into
the exhaust before the sensor. When the valve
switches, the real rich mixture will be suddenly
coming through and the sensor errors out. The
1.1 firmware is supposed to show a 'too rich'
error instead of sensor timing. Internally it
is the same error condition, but the firmware
checks if the last measurement before the error
was very rich (< 9.5
AFR), and if so, it shows “Too Rich” instead of a timing
error. If the mixture very suddenly gets too
rich, like when the air-valve switches, it does
not have time to make a rich measurement before
it errors out. Typically with an air-pump system
while pumping air before the sensor we see readings
of 16-22 AFR because of the air,
not 14.
In this case, many users suspect they are getting a timing error
from sensor overheating. However, it may not be overheating at all,
but running outside the measurement range of the sensor. To tune an
air-pump-equipped system you HAVE to disconnect the air-pump. Even
when it functions correctly, oscillations in the exhaust system can
move mixed-in air to the sensor area and cause erroneous readings.
One other related issue: We’ve seen cases where an aftermarket
ECU was used with a NB02 for closed loop control in conjunction with
an air-pump system. The aftermarket ECU was not set up to be air-pump
aware (few are) and therefore richened the mixture enough to make
its NBO2 show stoich with the air mixed in, while the engine itself
was of course running extremely rich.
Until next time... Keep On Tuning!
-Innovate Motorsports
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