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  1. Nah, I don't want to consider a different vehicle. I didn't buy it for the gas mileage lol.
  2. More about my application. I daily drive a 1999 Toyota 4Runner with 5vz-fe engine (3.4L V6 DOHC). Because the Toyota ECU is "locked", I do not have an HP Tuners or similar option. Any tuning is done with piggybacks to spoof the ECU. My truck has wideband "Air Fuel Ratio Sensors", and therefore always knows exactly what the AFR is. I have a piggyback made by Split Second called an Air/Fuel Ratio Calibrator. It reads MAP, and RPM, and allows you to alter the AFR Sensor's output to the ECU based on RPM and MAP conditions. Changing this AFR Sensor output allows the actual AFR to go leaner or richer at different RPMs and load ranges depending on what I want. At light load, and cruising RPMs (say between 1,000 and 2,000) I could command a lean AFR via piggyback. Below 1,000 RPMs I would leave the piggyback zeroed out so I'm not running lean at first startup. How lean (on lambda scale) should I shoot for if running on straight E85? Is there any benefit to lean burn if I can't command timing?
  3. @TD, with the lean burn, how much did you gain in fuel economy? If I'm not able to modify my timing values, but can command a specific AFR in closed loop, is this even worth doing?
  4. I have a 1999 Toyota 4Runner that I've been running E50 on with good results. Looking at my Long Term Fuel Trims, I don't think I can go much past E50. Stock fuel injectors are 245cc, so to make the E85 conversion I have a set of 315cc injectors to swap in that are 29% larger. These larger injectors should offset the higher fuel consumption requirements, and keep the ECU happy. My concern is cold starting in the winter time. The Toyota ECU is locked, no aftermarket tuning ability with programs like HP Tuners or Hondata like other cars have. I'm concerned that in cold temps, this non-FFV will not not be able to start on E85. An idea that occurred to me was to intercept the Engine Coolant Temp with a variable resistor (potentiometer), and make it report a colder temperature than what is actually occurring. The thought being that the ECU thinks it's colder than it actually is, and therefore injects more fuel during cranking. The potentiometer could then be zeroed out for normal operation after the engine starts. Has anyone tried or heard anything like this? I tried searching the forums and Google, but I don't think I was entering in the right search terms.
  5. I know this thread is super old, however I also have the 5vz-fe motor in my '99 4Runner, and I've been having good results with E50. The motor seems a bit more responsive, and stays in overdrive easier rather than downshifting.
  6. Yeah I like the baby bottles a little better, as I can stick the nozzle of the gas pump right in, instead of having to pour from different containers. I can put the top with the nipple back on to squeeze out an exact amount if I need to as well.
  7. So I started blending E85 into my '99 Toyota 4Runner at a Speedway station here in Chattanooga. I had read that in the winter time they switch the mix to E70 for easier vehicle starting. So I based my calculations assuming E70 and not E85. I decided to test the fuel to verify what percentage of ethanol was in the fuel. I bought a three pack of baby bottles from Walmart and took samples. One sample was E85, the other was 87 pump gas. I filled the bottles with 200ml of their respective fuel. E85 is in the green top on the left, regular pump gas in the blue top on the right: I was surprised how clear the E85 was. I filled the third bottle with 50ml of tap water from my sink: I added the 50ml of water to the 200ml of E85. I expected I would have 250ml total, but I didn't. It measured right at 235ml once the water was added. I'm assuming the alcohol absorbed some of the water? Assuming that the E85 did absorb the water, this indicates to me that I need to measure the gasoline portion of the mix only, since gas and water do not mix. Total volume = 235ml Separation line = 205ml Total gasoline = 235ml - 205ml = 30ml of gas Gas percentage = 30ml gas / 200ml total fuel = 15% gas 100% fuel - 15% gasoline = 85% ethanol I was surprised to see the ethanol content so high in the middle of winter time. For giggles, I conducted the same test with E10 87 octane pump gas: Total volume = 235ml Separation line = 60ml Total gasoline = 235ml - 60ml = 175ml of gas Gas percentage = 175ml gas / 200ml total fuel = 87.5% gas 100% fuel - 87.5% gasoline = 12.5% ethanol Hmmm, seems they're adding a touch too much ethanol to the gas ??
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