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engine cycles

Discussion in 'Gen 3 Prius Technical Discussion' started by Tombukt2, Mar 13, 2024.

  1. Tombukt2

    Tombukt2 Senior Member

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    So what Prius engines are Atkinson cycle I read somewhere where the first generation Prius the one NZ and the little coop was Atkinson cycle? The generation 2 doesn't seem to be but I don't know that for a fact It seems Atkinson cycle is all the two Z FXEs? All the way up through I don't know 2018 or 19? What about the new 2 l as that Atkinson cycle? Every time somebody has played around with these cycles Mazda with the Miller cycle orbit with the funny two cycle engine they made and there have been others they don't ever seem to take work very well what have you maybe the r&d isn't there I don't know but it seems you're out on the fringes with these kinds of things and maybe that's unnecessary I just want to stay away from all of this Atkinson cycle and that kind of thing that seems to be what's contributing to the issues with the generation 3 especially. Maybe the generation 4 gets it right or better by lowering the flow of EGR flooding the engine? I have no idea I do know that all of my other Toyota engines for the last 40 some odd years that were not any special cycles just regular four-cycle Toyota motors no need to list engine designations and whatnot anybody that knows the company knows what I'm talking about. To just ring out an extra half mile or even 2 mi to the gallon for something that's going to make my engine last only $170,000 mi I'd rather not have it personally that one to two miles to the gallon that I'm getting for that low mileage failure I'd rather have the high mileage.
     
  2. bisco

    bisco cookie crumbler

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    I thought they were all Atkinson, doesn’t seem to be an issue
     
  3. ChapmanF

    ChapmanF Senior Member

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    Every last single one. It's kind of the point of the car. The Atkinson cycle gives better fuel economy but lower peak power. The hybrid system makes up for that when you want the peak power.

    But no Prius engine ever used Atkinson's original design with the funky crankshaft and the piston moving different distances. Instead, Toyota just uses the intake valve timing to achieve the same effect.
     
  4. Tombukt2

    Tombukt2 Senior Member

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    Yeah I'm querying the guys over on Toyo to mods as to why no one's ever tried to stuff a 2ZZ engine in the generation 3 Prius and just try to keep from burying your foot all the time.? The regular 2ZZ non Atkinson doesn't seem to have head gasket issues similar to what goes on with the generation 3. I understand the Atkinson cycle I guess helps to detune the motor and I guess that's done so that there's some kind of balance between the output of the gas engine and the electric motors electric motor whatever. I was just curious to what would happen if you put a 2ZZ engine in the Prius of course you're going to fit all the stuff on the Z engine that you got to have I think they both have dual cam phasers and all of that sort of thing any of the sensors from the Prius Z engine to the Z engine of the say Corolla should bolt right up and go right into place and all that stuff I was just curious how well it would behave You're going to use this throttle body from the Prius and all that.
     
  5. Tombukt2

    Tombukt2 Senior Member

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    So maybe it in fact is the generation 3's flood of EGR running into the motor and when that little electric valve says so instead of the Atkinson cycle causing the problems with the head or temperature of the internal combustion process and then you have a failure too much heat not enough EGR gas getting in because of the clog and the cooler etc etc
     
  6. bisco

    bisco cookie crumbler

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    i thought it was incorrect software programming of the coolant pump
     
  7. ChapmanF

    ChapmanF Senior Member

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    i just keep popcorn handy and read tsbs