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35 mph EV barrier

Discussion in 'Gen 2 Prius Accessories & Modifications' started by drjake, Dec 27, 2011.

  1. cwerdna

    cwerdna Senior Member

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    Not in terms of EPA city nor EPA combined mileage.
     
  2. drjake

    drjake New Member

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    My plan after it warms up in the spring is to look at pin 19 (spd1 see attachment) on the hybrid controller and if my thinking is correct it will be a pulse of varying frequency
    then simulate the frequency that is present at 33 mph then the hybrid controller
    will think it is going 33 mph no matter how fast you are going.
    AND I KNOW ABOUT YOUR BURNING GAS TO MAKE ELECTRIC YADA YADA YADA
    This is step one to make a plug in if any one wants to help fine I don't need to hear about can't be done because some companies are doing it and charging an arm and leg to have it done
     

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  3. bisco

    bisco cookie crumbler

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    sorry, can't be done. okay, i guess anything is possible if you put your mind to it.:nerd::p
     
  4. drjake

    drjake New Member

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    Bisco
    would you care to elaborate why it can't work
    I just read a good thread about defeating the nav speed sensor why would it not work for the
    Hybrid drive?
     
  5. suprat04r

    suprat04r Junior Member

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    i'm not sure if i know what i'm talking about (i just bought the prius 07). but i can drive without the gas motor above 35mph, if i let off the throttle and very gently feather the throttle (or as you guys would call it coast?)
     
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  6. seilerts

    seilerts Battery Curmudgeon

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    Under some circumstances, you can lock out the gas engine by forcing the vehicle to go in EV mode only. But above 34 mph, it will drop out of EV mode, and the gas engine will come on.

    Dr. Jake, you would be testing an assumption that (1) it is vehicle speed, rather than MG1 rpm, which results in car dropping from EV mode. My own personal belief is that EV mode drops when MG1 hits 5000 rpm.
     
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  7. bisco

    bisco cookie crumbler

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    well, it's not that it can't work. it's just that, if you can make it work, i'll give you one of these: :hail: :D
     
  8. bisco

    bisco cookie crumbler

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    if you don't have a scangauge, the mfd won't tell you that the engine is spinning but not burning gas. it does reduce your mpg's tho.
     
  9. usnavystgc

    usnavystgc Die Hard DIYer and Ebike enthusiast.

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    The only way you can really find out is by trying it. I'm not an expert but this MAY work to get it above 35mph but there are other sensors (namely MG1 rpm sensor) that will not let it go above 52 mph (I'm uncertain if MG1 has a seperate sensor or if SPD1 is the input). The bottom line is Toyota limited MG1's max rpm for a reason (most likely for the safety of the MG). Make sure you take this into account so you don't fry an MG. According to people I've talked to, PIS has designed software to account for this (I don't know how but, I heard they did) and their system allows you to go 70+mph in EV mode. I'm fairly certain PICC's system also allows 70+mph in EV.

    I would like to point out (as I always try to do) that there are dangers to mods and all should be approached with caution and the knowledge that you might screw something up. I say all of this not to discourage you but to encourage you to try to take all things into account so you don't cost yourself a lot of money. With that in mind, if you're willing to take the risk, and you discover something, pls share with us.
     
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  10. drjake

    drjake New Member

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    Thank you all for the input I will look at the MG1 input as well and look at the wiring diagram to see were this signal comes and goes.
    I for one would be happy at 52 MPH in EV mode if I can achieve that I will look in to adding battery capacity and a charging system.
    Remember if man made it man can hack it.
     
  11. seilerts

    seilerts Battery Curmudgeon

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  12. drjake

    drjake New Member

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    Could you point out what page of the wiring diagram MG1 is on I could not find it
     
  13. wrexed03

    wrexed03 New Member

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    Had a play with my GENII today curiosity got the better of me re the speed limitation in ev mode. I removed the ecu fuse and took it for a drive.
    Managed to get past the speed limitation on my vehicle using just electric.
    Got to 58kmh without any issues till it started running out of juice.
    Had to put the fuse back in after stopping so engine could kick in and start charging the HV battery.
    Only issue with this is it gives you the triangle of death. Only way to clear it was disconnecting the 12v battery.
    Thought i would post incase anyone wanted to know the result.
     
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  14. Jimbo69ny

    Jimbo69ny Active Member

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    I think in the right situation, removal of the 34 mph limit would be useful. I live in Ithaca NY where there are a lot of hills. I live in the valley so every time I come home I go down a hill at highway speeds. I could coast down in Neutral but if I do I wont be recharging my batteries. If I drive down the hill in Drive the gas engine will kick on because of the speed im going. If I could limit the car to propelling in electric only I have to assume that it would be able to do that using very little power. Plus I would be able to recharge as I drive down the hill.

    I am going to search to find a way to get rid of the cut off without damage.
     
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  15. NortTexSalv04Prius

    NortTexSalv04Prius Active Member

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    Okay
    The Gen 3 has the ability to go "EV" . The limit on the Gen 3 is from 10 to 14 miles in pure "EV" at a given speed above or below "34 mph". On the Gen2 most owners that want over "34" "EV" go with a PHEV to give the vehicle the ability and capacity to do so.
     
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  16. NortTexSalv04Prius

    NortTexSalv04Prius Active Member

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    I am not sure MG1 and MG2 will go neutral............