"Technology for Tuners" Newsletter
This is Innovate Motorsports' "Technology for Tuners" Newsletter,
Issue #4. 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) AuxBox Released to Production!
2) XD-1 (Digital Display) Product Update
3) LM-1 gets good press
4) Tuning Tip: When to Perform a Heater Calibration
5) Application Note: You CAN be too Rich
The AuxBox is released to production!
The LMA-3, also known as the AuxBox, is released from
engineering. This device attaches to the auxiliary input
of the LM-1 and allows a user to log and analyze 5 critical
engine metrics in addition to the air/fuel ratio native
on the LM-1. The AuxBox makes the LM-1 into a complete
tuning kit, allowing the user to capture, view, and analyze
data on all 6 channels that the LM-1 can log internally.
Correlating AFR, RPM, MAP, and CHT, for example, is essential
when tuning piggy-back fuel controllers, ECU programmers,
aftermarket ECUs, or racing carburetors.
The 5 internal sensors are intended for capturing Manifold
Air Pressure (MAP or Boost), Cylinder Head Temperature
(CHT) or Exhaust Gas Temperature (EGT), RPM conversion
(from a tach signal or inductive clamp), Acceleration,
and Injector Duty Cycle (or Dwell). The internal MAP sensor
is a 3-bar absolute pressure sensor, providing accurate
data up to 44.1 PSIA. The temperature measurement circuit
features a K-type thermocouple. The internal accelerometer
features 2 axis measurements for a variety of mounting
Another key application of the AuxBox is road testing.
Even a dyno doesn’t provide as much real data as
road testing. Factors like air flow, side force, and load
vary significantly on a real road. With an AuxBox, a user
can log 6 channels, in multiple sessions, for up to 44
minutes. Then, back at the garage, simply connect the LM-1
to you PC and view all of you log data. Use LogWorks to
view fuel mapping, perform statistical analysis, overlay
graphs, and playback a log on the virtual gauges. You can
also view realtime data on LogWorks’ gauges if you
want to take your laptop on the road.
The AuxBox also includes 5 external inputs for connecting
external sensors in lieu of the internal sensors. This
allows users to log data from external sensors like TPS
or suspension data. Each input can also be configured with
additional thermocouples, allowing multiple EGT channels.
The AuxBox ships with mounting hardware, a 6’ thermocouple
wire, the LM-1 connecting cable, and the user manual.
SPECIAL OFFER: For existing LM-1 owners, we are
offerring a limited-time offer. Enter coupon code "LM1VIP" (as
in, LM-1 V.I.P. ) to get special pricing of $229. (This
offer will end as soon as we've shipped the first production
run of 500 units, or on Sept. 30, whichever comes first.
This newsletter goes to more than 4000 existing LM-1
customers who've signed up on the mailing list, so get
yours now if you want in on the special offer. After
the introduction, the AuxBox will be $249.) Click
here to buy now.
Digital Display Product Update
The Innovate XD-1 dash-mountable Digital Display is in
the final stages of testing, and will be released this
quarter. The entire gauge will be a mere .550” thick,
so it will be possible to mount even in surface mount configurations.
The display will feature a 3 character LED display, "Record" button,
and a programmable digital needle. The body is a billet
aluminum bezel. It will be available in a variety of color
combinations, and is targeted to retail for $189, pending
final product release.
LM-1 in Modified Magazine, Chevy Rumble, Muscle
Machines, and more
The LM-1 has been receiving quite a bit of positive press
recently. This year to date a partial list of magazines
featuring the LM-1 includes Car Craft, Modified, Chevy
Rumble, Circle Track, Import Tuner, Hemmings’ Muscle
Machines, Muscle Car Enthusiast, Performance Business,
Performance Racing Industry, High Performance Pontiac,
and Family and Performance Boating. Check the site in a
few weeks for links to, or reprints of, most of these informative
Tuning Tip: When to Perform a Heater Calibration
The LM-1 has two calibrations- one for the sensor heater
and one for free air. In general, it’s only necessary
to calibrate the sensor heater the first time you use a
new sensor, while the free air calibration is required
more frequently. Free air calibration will correct for:
1) A change in atmospheric pressure (i.e. going from sea
level to 6,000 ft. above for a race); or 2) Sensor wear
(i.e. regular use for hundreds of hours).
Heater calibration detects and stores the impedance characteristics
of a new sensor. Generally these characteristics don’t
change with wear, however some forms of carbonization can
impact the impedance of the sensor. The most common problematic
carbonization comes from the use of leaded gas. If you
see an error #4 (Pump cell circuit open) after using the
LM-1 with leaded gas, you probably need to perform a heater
recalibration. If you use LM-1 regularly with race gas,
we recommend keeping a backup sensor in your tool box,
and performing heater recalibrations more frequently.
To clear the heater calibration data, simply connect the
LM-1 to 12V and power it on for 10 seconds without the
sensor connected. Then turn it off, connect the sensor
and power up again. The LM-1 detects the sensor as new
and performs a full heater calibration. Of course don’t
calibrate the heater with the sensor in very hot exhaust
or in an overheated state.
Application Note: You CAN be too Rich
By Klaus Allmendinger, VP of Engineering, Innovate
Many people with turbochargers believe that they need
to run at very rich mixtures. The theory is that the excess
fuel cools the intake charge and therefore reduces the
probability of knock. It does work in reducing knock, but
not because of charge cooling. The following little article
First let’s look at the science. Specific heat is
the amount of energy required to raise 1 kg of material
by one degree K (Kelvin, same as Celsius but with 0 point
at absolute zero). Different materials have different specific
heats. The energy is measured in kJ or kilojoules:
Air ~ 1 kJ/( kg * deg K)
Gasoline 2.02 kJ/( kg * deg K)
Water 4.18 kJ/( kg * deg K)
Ethanol 2.43 kJ/( kg * deg K)
Methanol 2.51 kJ/( kg * deg K)
Fuel and other liquids also have what's called latent
heat. This is the heat energy required to vaporize 1 kg
of the liquid. The fuel in an internal combustion engine
has to be vaporized and mixed thoroughly with the incoming
air to produce power. Liquid gasoline does not burn. The
energy to vaporize the fuel comes partially from the incoming
air, cooling it. The latent heat energy required is actually
much larger than the specific heat. That the energy comes
from the incoming air can be easily seen on older carbureted
cars, where frost can actually form on the intake manifold
from the cooling of the charge.
The latent heat values of different liquids are shown
Gasoline 350 kJ/kg
Water 2256 kJ/kg
Ethanol 904 kJ/kg
Methanol 1109 kJ/kg
Most engines produce maximum power (with optimized ignition
timing) at an air-fuel-ratio between 12 and 13. Let's assume
the optimum is in the middle at 12.5. This means that for
every kg of air, 0.08 kg of fuel is mixed in and vaporized.
The vaporization of the fuel extracts 28 kJ of energy from
the air charge. If the mixture has an air-fuel-ratio of
11 instead, the vaporization extracts 31.8 kJ instead.
A difference of 3.8 kJ. Because air has a specific heat
of about 1 kJ/kg*deg K, the air charge is only 3.8 C (or
K) degrees cooler for the rich mixture compared to the
optimum power mixture. This small difference has very little
effect on knock or power output.
If instead of the richer mixture about 10% (by mass) of
water would be injected in the intake charge (0.008 kg
Water/kg air), the high latent heat of the water would
cool the charge by 18 degrees, about 4 times the cooling
effect of the richer mixture. The added fuel for the rich
mixture can't burn because there is just not enough oxygen
available. So it does not matter if fuel or water is added.
So where does the knock suppression of richer mixtures
If the mixture gets ignited by the spark, a flame front
spreads out from the spark plug. This burning mixture increases
the pressure and temperature in the cylinder. At some time
in the process the pressures and temperatures peak. The
speed of the flame front is dependent on mixture density
and AFR. A richer or leaner AFR than about 12-13 AFR burns
slower. A denser mixture burns faster.
So with a turbo under boost the mixture density raises
and results in a faster burning mixture. The closer the
peak pressure is to TDC, the higher that peak pressure
is, resulting in a high knock probability. Also there is
less leverage on the crankshaft for the pressure to produce
torque, and, therefore, less power.
Richening up the mixture results in a slower burn, moving
the pressure peak later where there is more leverage, hence
more torque. Also the pressure peak is lower at a later
crank angle and the knock probability is reduced. The same
effect can be achieved with an optimum power mixture and
more ignition retard.
Optimum mix with “later” ignition can produce
more power because more energy is released from the combustion
of gasoline. Here’s why: When hydrocarbons like gasoline
combust, the burn process actually happens in multiple
stages. First the gasoline molecules are broken up into
hydrogen and carbon. The hydrogen combines with oxygen
from the air to form H2O (water) and the carbon molecules
form CO. This process happens very fast at the front edge
of the flame front. The second stage converts CO to CO2.
This process is relatively slow and requires water molecules
(from the first stage) for completion. If there is no more
oxygen available (most of it consumed in the first stage),
the second stage can't happen. But about 2/3 of the energy
released from the burning of the carbon is released in
the second stage. Therefore a richer mixture releases less
energy, lowering peak pressures and temperatures, and produces
less power. A secondary side effect is of course also a
lowering of knock probability. It's like closing the throttle
a little. A typical engine does not knock when running
on part throttle because less energy and therefore lower
pressures and temperatures are in the cylinder.
This is why running overly-rich mixtures can not only
increase fuel consumption, but also cost power.
Until next time... Keep On Tuning!
NOTE: If you found any of this useful,
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you can use the link at the bottom of the original email.