You got one of those boxes which "cheat" the fuel injectors?
Hi SD:
I'm not sure what you mean by "cheat". The RLTC (traction control) works by being a man-in-the-middle between the ECU and the injectors, and sometimes elects to modify the signals
> When wheel spin is detected the engine power is reduced, by cutting a
> single injector pulse, until grip is resumed. This occurs in a thousandth
> of a second, and appears to the driver as a slight misfire with no loss in
> acceleration.
>...
> Racelogic Traction Control prevents lean burn by removing 100% of the
> pulsed fuel delivery – essentially the affected cylinder takes a gulp of
> fresh air; the in-cylinder temperature remains virtually unaffected.
>
> Prolonged fuel cut on one particular cylinder would cause scavenging of
> the petrol lining the inlet tracts, and when the next full fuel pulse
> arrived, it would be partially reduced in quantity by the re-wetting of
> these tracts. RL Traction Control rotates cylinder cutting to prevent this
> situation from occurring.
www.racelogic.co.uk/index.php/en/other-products/traction-control?start=3Maybe that's what you mean by "cheating" the fuel injectors.
But for E85, the situation is quite different.
The reason I want to use E85 is mainly:
> ...it allows the motor to run MUCH cooler. Typically we see 20 degrees
> drop in water temperature
www.whiteracing.com/e85.htmlThis will be good for the TX Mile. The TX Mile is like four 1/4 mile drag runs all put together, and helping the motor from melting down is a great benefit.
and it has a higher octane than regular gas:
> E85 has 105 octane.
www.change2e85.com/servlet/Page?template=MythsI don't know if I'll be taking advantage of that higher octane. I don't want to build the motor around requiring E85. I want it to be able to use gas or E85 (or a mixture), and then get the benefits of reduced engine cooling when running with E85.
> ethanol offers up roughly 30 percent less Btu heat-output per pound of
> fuel compared with gasoline. That means to make the same power, we
> have to use 30 percent more fuel.
Read more:
www.carcraft.com/techarticles/ccrp_0702_e85/viewall.html#ixzz1t2B3oy9dSo to use gas / E85 / or a combination (E85 is already a combination of gas / ethanol, and even straight from the pump may not be a consistent ratio), it seems that a "flex fuel sensor" is the ticket.
FAST XFI has the ability to read the sensor (used by GM in its E85 flex-fuel vehicles), and then adjust the injector timing to get the right amount of fuel in the combustion chamber.
Here are some notes and pic I wrote 2 years ago.
GM flex-fuel sensor:
www.efi101.com/forum/viewtopic.php?t=5485&sid=752a23f2fa6b436f3c8a5dc48115afe7> The Zeitronix is a GM flex sensor.
> We have been splitting the return line and running part of the fuel
> through the sensor. The high horsepower stuff will not flow enough fuel
> through the sensor by itself but we really don't care, we are just looking
> for alcohol content and not the fuel temp. The FAST XFI can use the
> Flex Fuel sensor to change the target fuel energy constant in it's table
> and modify the fuel curve based on the percent of alcohol feeds back to
> the ECU. This in conjunction with the wideband you can switch fuels
> and still use the same map.
> I drilled a couple passages under the 3/8" npt so that one runs to and
> from the flex fuel sensor and one goes straight through to the return
> line.
Another installation:
This is the FAST XFI constant the sensor changes:
www.turbobuick.com/forums/e85-technical-forum/231593-e85-fast.html> Fuel Energy Constant
>
> This parameter is a constant that defines the energy properties of a
> given fuel as the difference between it and gasoline (see table below).
> This strategy allows us a comprehensive range of fuel types and
> mixtures. The XFI ECU will compensate the fuel delivery based upon this
> parameter. While using the Lambda display mode will be more uniform in
> the display of the air/fuel ratio with different fuels, C-ComXFI will
> otherwise display all air/fuel ratios adjusted to the Fuel Energy
> Constant. Please note that the injector flow rate is still entered as lb/hr
> but as normally rated with gasoline.
>
> Fuel Energy Constants (FEC) for Common Fuels
> Fuel Type FEC Stoichiometric A/F
> Compressed Natural Gas (CNG) 1.17 17.2:1
> Liquid Propane (LP) 1.07 15.7:1
> Gasoline 1.00 14.7:1
> Methyl Tertiary Butyl Ether (MTBE) .796 11.7:1
> 85% Ethanol/Gasoline Mix (E85) .680 10.0:1
> Ethanol (ETOH) .612 9.0:1
> Methanol (MEOH) .439 6.45:1
www.efi101.com/forum/viewtopic.php?t=5485&sid=752a23f2fa6b436f3c8a5dc48115afe7> Here is a schematic of the sensor
>
www.zeitronix.com/Products/ECA/Ethanol%20Content%20Analyzer%20Instructions.pdf> The signal wire needs to go to the AUX Descrete Shaft wire Pin A6
>
> 2.1.20 AUX SHAFT
>
> This connector is for the auxiliary shaft sensor input circuit. The FAST
> VSS and auxiliary shaft harness kit (part # 30-1403)will supply you with
> the harness, sensor, and magnets to monitor things such as turbo speed
> and torque converter/clutch slippage.
>
> Pin A – Inductive return, black (A2)
> Pin B – AUX discrete, orange (A6)
> Pin C – Discrete return, black/white (A13)
> Pin D – Aux inductive, purple (A17)
www.megamanual.com/flexfuel.htm> The fuel sensor uses a microprocessor to measure the ethanol
> percentage and fuel temperature, which it uses to produce and output
> signal. The fuel sensor signal is a square-wave voltage signal. The signal
> varies in both frequency and pulse width:
> * The frequency of the signal indicates the ethanol percentage. The
> output frequency is linear with respect to the percentage of ethanol
> content in the fuel. The PCM provides an internal pull-up to five volts on
> the signal circuit, and the fuel sensor pulls the 5 volts to ground in
> pulses. The normal range of operating frequency is between 50 and 150
> Hertz:
> o 50 Hertz indicates 0% ethanol, and
> o 150 Hertz indicates 100% ethanol.
> * The pulse width indicates the fuel temperature. The normal pulse
> width is between 1 and 5 milliseconds:
> o 1 millisecond indicates -40°C (-40°F), and
> o 5 milliseconds indicates 125°C (257°F).
www.turbobuick.com/forums/e85-technical-forum/239731-fuel-sensor-xfi.html> David Page with FAST gave the folllowing info to me today:
>
> The GM Flex-Fuel Sensor PN is 12570260.
>
> The wiring directions are, "The wiring is straight forward...power and
> ground to the sensor, signal to the XFI's Aux. (shaft) discrete input."
>
New flex fuel sensor and harness available for about $650 from
www.whiteracing.com/Available here, with harness for $400
www.zeitronix.com/order/order.htm#ECAThese notes are 2 years old, but it was good to get them out and refresh my memory and store here for future reference.
your friend in computer memory,
arthur