"Technology for Tuners" Newsletter
This is Innovate Motorsports' "Technology for Tuners" Newsletter,
Issue #6. 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) LM-1 Firmware version 1.41 is released
2) New products: Carrying Case, Window Clamp, and Autronics
3) Visit us at the PRI show
4) Testimonial T-shirt contest
5) LC-1 & XD-1 update
6) Tuning Tip- Ethanol content
LM-1 Firmware version 1.41 is released
firmware update for the LM-1 fixes a random and rare bug
that produces momentary lean spikes/glitches. If
you’ve seen lean glitches in you log files, and
you know that you aren’t experiencing missed ignition
events, definitely install this firmware
products: Carrying Case, Window Clamp, and Autronics
The MTS (Modular Tuning System) Carrying Case is a durable
plastic case, designed to hold the LM-1 and all accessories
included in any configuration of the MTS kits. The Window
Mount allows you to have the LM-1 mounted to your windshield.
This will help provide a better view of
the display while road tuning.
better interface with Autronics’ ECUs, we’ve
developed a custom interface cable. This is essentially
a modified analog output cable that includes some active
circuitry to precisely match the input expectations of
the ECU. The SKU is #3745, and it’s available on
our web site for $59.
Visit us at the PRI show
The PRI show in
Indianapolis is part 2 of the annual show madness. We’ll
be at booth #5214, showing off the new products, playing
the new training videos,
and meeting customers. If you’re coming to the
show, drop by and say hi to Klaus, Cort, and Patrick.
Write a quick testimonial, take a cool photo (you and
an Innovate product in use), and send it in to us (email
or snail mail). Each month we’ll select the best
ones, and send the winners some Innovate swag- long-sleeve
T-shirts, hats, Polo shirts, etc. And you might even see
yourself in a national magazine ad.
LC-1 & XD-1
The much anticipated LC-1 (aka “Lambda Cable”)
beta units are scheduled to ship in the coming weeks, with
full product release in January. But, as usual, until full
release, we can't commit ship dates. The XD-1 Digital Universal
Gauge (also much anticipated) is tracking basically the
same. All of the new products will be in full production
well in advance of the 2005 race season.
Tuning Tip: Ethanol Content
We've had a few reports where users could not “nail
down” their tune on the street with the LM-1. The
AFR's would jump about 0.5 AFR across the WOT band even
in the same weather conditions in the space of a few days.
Instead of holding a tune, the engine seemed to slowly “yodel.”
Naturally the first thing to blame was the LM-1. But it
turned out that the users filled up at different gas stations,
sometimes filling up on gas that had 10% ethanol mixed
in. As expected, when Schnapps is mixed with cars, things
get a little complicated.
If ethanol (stoich AFR of 9) is mixed with gasoline (stoich
AFR of 14.7) the resulting gas has a lower stoich AFR than
'pure' gasoline. As the fuel injection is tuned to mix
a certain amount of fuel for a given amount of air, the
resulting mixture would be leaner when using a fuel with
lower stoich AFR.
This can be calculated:
sAFR = (%ofAdditive * sAFRadditive + (90-%ofAdditive)
* sAFRgas) /100
sAFR is resulting stoich AFR
%ofAdditive is amount in % of mass of additive (ethanol)
sAFRadditive is stoich AFR of additive (9 for ethanol)
sAFRgas is stoich AFR of base gasoline (14.7)
For a 10% mixture of ethanol to gasoline by mass the resulting
stoich AFR is 14.13
So, for an engine that's tuned to certain AFR at a certain
load and RPM on straight gas, the resulting (gasoline equivalent)
AFR when running the mixture can be calculated as:
new AFR = tuned gas AFR * (gasoline stoich ratio) / blend
An engine tuned to 12.5 gas AFR will run at the equivalent
of 13 gas AFR with a 10% ethanol blend. This is what these
people were seeing.
Of course, when running in closed loop, the engine will
run at 14.13 AFR instead of 14.7. O2 sensors (incl. widebands)
don’t measure AFR, but Lambda. Lambda is defined
as actual AFR/stoich AFR. It's a ratio. In closed loop
part throttle the engine is just running at Lambda 1.0,
regardless of fuel. The same would be true for other Lambda
values when running closed loop at WOT using a wideband.
The engine would run at the tuned Lambda and everything
would be fine. Open loop systems would need to be retuned
for alcohol blends though.
Until next time... Keep On Tuning!
NOTE: If you found any of this useful,
and you'd like to share it with a friend or colleague,
you can use the link at the bottom of the original email.