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100% e85 on cobb bms flash?
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11-29-2012, 03:45 PM | #1 |
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100% e85 on cobb bms flash?
Found this on YouTube. Maybe someone can explain or the owner can chime in? 100% e85 without upgraded fuel system? Me like...
Copied From my phone...not sure how link Looks..sorry
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11-29-2012, 04:06 PM | #2 | |
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I tihnk above 60%/40% E95/93(91) without flex fuel wires will trip ecu sensors. I dont even think our fuel pumps can handle it 100% without maxing them out. |
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11-29-2012, 04:43 PM | #3 |
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More than likely he's just running the BMS flash and not 100% e85. The added fueling from the flash takes care of trims and a few other things, but with 100% e85 you would run into LPFP not being able to maintain the volume required to support the HPFP after shifts.
FFTEC just posted a picture of the LPFP booster on facebook "Vishnu Performance Systems". I'm running this pump and have been for the past 3 weeks. I run 100% e85 with no LPFP codes. I was skeptical at first, but I was trapping 150+ at Shift S3ctor and didn't have any fueling issues running 100% e85. BUT.... Regardless of what tune you're running, your DME fueling tables need to be updated to take advantage of this. Otherwise you'll still be maxing your trims. |
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11-29-2012, 04:49 PM | #4 | |
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11-29-2012, 05:15 PM | #5 |
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11-29-2012, 06:00 PM | #7 | |
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Mike |
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11-29-2012, 06:30 PM | #8 | |
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11-29-2012, 07:12 PM | #9 |
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11-29-2012, 07:25 PM | #10 | |
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11-29-2012, 08:25 PM | #11 | |
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Did I need the pump? No... I could have dump Methanol at the engine and it probably would have been fine. But most people including myself doesn't want to use Methanol, at least in my case not all the time. Honestly, I haven't taken the time to log debug byte 4 sense I got home. With the rain and cooler weather, it's really hard to log due to wheel spin. I'm sure there will be a thread specifically for this and technical data will be provided. |
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11-29-2012, 08:31 PM | #12 | |
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11-29-2012, 09:55 PM | #13 | |
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That being said, I was hoping for something a little more professional than a booster pump slapped on to compensate for the stock pump. I will wait to pass judgment on this inline booster pump, but to me the concept sounds more like an "aftermarket solution" that doesn't integrate properly with the OE fuel system. If the stock pump doesn't flow enough it should be replaced with one that does. Maybe I am missing something, guess we will see. |
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11-29-2012, 11:02 PM | #14 | |
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The ability of a fuel delivery system to maintain a specific pressure (in PSI) is an important factor when analyzing a fuel system. It should not be confused with volumetric or ability to deliver a specific amount (in Gal. per minute or Litters per minute) of fuel. As a rule of thumb, when a system can not maintain a specific pressure, the vehicle will probably run very bad or not run at all. On the other hand, it is quite common to see vehicles with good fuel pressure and have performance problems due to a lack of fuel volume. Good fuel volume is the system’s ability to maintain a specific quantity or volume regardless of vehicle operation and that is the key point that everyone seems to overlook. When two (or more) pumps are arranged in serial their resulting pump performance curve is obtained by adding their heads at the same flow rate as indicated in the figure below. Pumps in series are used to overcome larger system head loss than one pump can handle alone. * For two identical pumps in series the head will be twice the head of a single pump at the same flow rate - as indicated in point 2. With a constant flowrate the combined head moves from 1 to 2. Note! In practice the combined head and flow rate moves along the system curve to point 3. * Point 3 is where the system operates with both pumps running * Point 1 is where the system operates with one pump running So I'm not saying that for most the replacement of the LPFP will fix the issue if the volume of fuel is increased by the replacement of the old pump. But when your system demands more volume that a single pump can deliver, adding a booster pump will increase the flow rate required to sustain the HPFP at peak demand. |
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11-29-2012, 11:19 PM | #15 | |
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11-29-2012, 11:20 PM | #16 |
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I don't really understand are you talking about low fuel pressure flow or high fuel pressure flow? They are different things.
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11-29-2012, 11:29 PM | #17 |
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Yes, two very different things. Your LPFP feeds the HPFP and if it can't maintain the required pressure, your DME will trigger a LPFP code. Replacing the LPFP could increase the pressure and volume, but eventually you will exceed the volume required to supply the HPFP with a single pump.
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11-29-2012, 11:37 PM | #18 | |
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11-29-2012, 11:52 PM | #19 | ||
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The info you copied somewhere from the internet is correct. What that stipulates is that running pumps in series jacks up the pressure and thus only flows more if you are losing pressure. The upgraded LPFP is NOT losing pressure. Are you suggesting we raise the stock pressure limit (I am not necessarily opposed, just genuinely curious)? Btw, if you go back to the website you were just on and look at the schematic right below it, you will see that two pumps in parallel is a much more effective method of increasing flow rather than pressure... Kind of surprised you didn't post that. http://www.engineeringtoolbox.com/pu...ial-d_636.html Quote:
This statement is patently false. Are you seriously saying there isn't a single pump in the world that can flow enough to feed our HPFP??? There is and its already out there running. Its the pump Walbro designed for running E85 on which there are DIYs for... Even if its not that pump, to say there isn't a single pump that can flow enough is just plain wrong. Last edited by ign335i; 11-30-2012 at 12:00 AM.. |
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11-30-2012, 09:49 AM | #20 | |
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11-30-2012, 09:58 AM | #21 |
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No one is telling you that you can't go out and buy the biggest pump you can find and customize it to fit your car. You have options and that's why I can't understand why people keep making a big deal out of this. If your LPFP is failing, replace it. You can replace it using the DIY with the Walbro E85 pump, or pickup a new OEM. Or you now have the option of running a plug-n-play inline booster pump that goes inside your tank. It's very simple, but you have to make your own choice. I can tell you all day long that it works for me and I have it installed and have tested it. Or you can listen to someone assumptions because they are skeptical, haven't tested it, but still think they know better. Trust me, I was skeptical also... but again, it works...
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11-30-2012, 10:28 AM | #22 | |
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