What I have learned about 3rd gen transmission.

There are some values that need to be cleared with the Techstream.

 

And it is an exceptionally smooth, continuous system.

 

That is exactly what the term Atkinson Cycle refers to, and has always referred to. They're not claiming it's an actual Atkinson engine from the 1800s, obviously. Toyota has been using it since the Prius came out in the '90s and several other automakers use it as well, almost exclusively in hybrids. It was never marketed as strongly as it has been with the Tacoma because, probably, hybrid owners don't care about engine technology. If your claim is that being in the Atkinson cycle doesn't reduce power output, you don't really understand what it's doing in mechanical terms.

The difference between my claim and the claim that there's a problem in the valve body that results in a bubble, or whatever, is that every bit of marketing and technical documentation about this truck indicates that it uses the Atkinson cycle and, if you understand how it works, logic dictates that when power output is at a minimum is when it's active. Therefore, my claim is self-evident.

Here's something else that's self-evident: by the time you give enough throttle for it to get out of Atkinson, you're also giving it enough to downshift out of OD.

 

You are partially correct. See the below link for a description of the Atkinson cycle. I would not use Wikipedia or magazine articles for your facts. There is a lot of marketing jargon in there. See the patent.

Atkinson cycle:

https://www.google.com/patents/US367496

 

And you are correct, when the intake camshaft is at maximum retard, what you are calling Atkinson cycle, the torque is minimal.

Of course I understand that DSM. I just explained the whole system off the top of my head.

 

I am fully correct, you're not teaching me anything. This patent is for an Atkinson engine. Toyota does not use an Atkinson engine. They use an Atkinson cycle which mimics the valve timing of an Atkinson engine but has nothing in common with the engine design, otherwise.

 

I know, not sure why everyone says the transmission hunts all the time. Mine goes into a gear and stays there just fine.

 

I stand corrected. You are correct in your above statement. I was not aware that the Atkinson cycle term could be used to describe the new vvti strategies.

 

Ever drive up a mountain?

 

All the time. I live in Utah

 

He has a MT so not relevant to AT conversation.

 

Pull it and report back if it sucks less.

 

POS truck, fuck Toyota.

 

This is a great resource, Ill spend some time going thru this thank you!

Look man you obviously understand the method of variable valve timing in this truck, but when you state that these trucks won't accelerate in 5th gear because it's permanatly in an atkinson cycle condition, I get skeptical. I asked you to provide me with something technical to back it up, and you say that you can literally feel it. I get skeptical x2.

Speed limit on the highways here is 60mph, so I doubt i'll get to test your theory any time soon. All i'm saying is
my drive by wire truck howls, the hood shakes, pedal buzzes, interior rattles, and it makes it hard to "feel" anything so "self evident" as what you're describing. Luckily black sabbath at about 40 on the volume knob has made this truck much more enjoyable in any gear.

 

Also,
I am pretty sure (this is speculation) that the truck does not take discrete steps into an out of Atkinson. I think it is a continuous movement of intake camshaft position. The transition is very smooth. I have been meaning to capture a data log on the Techstream but I've been very busy.

 

Yeah but, you ever drive up a mountain... on weed?

 

Who's that guy in the bushes?? RED TEAM GO, RED TEAM GO!

 

Thats what I figured.

Just picked up my truck from having an oil leak fixed and I'm 99% sure the battery was unplugged due to the fact that my trip was back at 0 and it still drives like junkish. But I will try anyways!

 

This is spot on. It seems rare for anyone complaining about a "gutless" engine or a lousy transmission to reference the Atkinson cycle. No one should have bought this truck expecting a completely traditional driving experience. Not with an engine that deliberately reduces its effective displacement when cruising. It may be, as you suggest, that a lot of people didn't understand this, or it could also be that they did understand it but bought the truck anyway, somehow expecting that it wouldn't matter. This is a Toyota Tacoma, after all, and, well, Toyota wouldn't really do this to its loyal fans, would it? They did, but no one should say they didn't make the Atkinson cycle clear to anyone who read the marketing tracts, and the implications of it should have been evident. It may be that Toyota didn't do the best job of coordinating the transmission software to the Atkinson engine, but smoothing out the engine's Atkinson cycling via a transmission would probably cancel out the fuel savings. And I had expected those fuel savings to be better than they turned out to be. With a lower displacement engine, significantly reduced wind resistance, and the Atkinson cycle, I thought we'd see a few more MPG. But the EPA data should have dashed the expectations of anyone like me. So all the information was available before the truck came on the market. Do I like it? Not particularly. But I've adjusted over time. I just hope Toyota didn't change anything that compromises reliability and longevity. That's really why I bought this truck as compared to a different one.