2005 Prius engine into 1986 MR2: mk1 1nzfxe Prius swap (gas only)

[rmay635703]

Originally Posted by Sean.Heihn

Don't those little Kei trucks/vans already get 50+ MPG? Atkinson cycle has horrible low end torque, that's why you only see it in hybrids were the electric motor can supply the low end torque to get moving. So I don't think it'd work well in a cargo vehicle.

Yes & no, my kei van is an EV with some unfortunate issues at the moment. As a gasser in the UK 32mpg US is much more likely, I have not been able to find the 660cc fuel economy from japan (aka an 05 move 5sp, too bad the japanese language is still a barrier) Also low end torque would not be an issue on a 2000lb van that originally came with a 2cycle engine (not much low end on a 2 cycle)

Originally Posted by Sean.Heihn

Now what I'd do is buy a 1NZ-FXE (or a small diesel) and make a 'battery pack-less' series hybrid. Have the engine drive a generator to supply electricity for the traction motor/s, with start/stop, a small battery pack to supply power to start the engine/power the traction motor/s while the engine spins up, regenerative braking to charge the battery pack. You'd cut down on weight and cost without the huge battery packs in current hybrids, plus with hub traction motors you'd cut down on complexity, cost, and power transmission loss and the engine, since it only provides power to the generator, can spin at the peak efficiency rpm range. Basically this is how diesel/electric locomotives work.

I would like to convert the Miles zx40 ev to a volt-like vehicle, this would reduce the affects of some unfortunate battery degredation from a collision.

Running it at 42 volts of damaged batteries is no fun.

Ah well, I wonder why the motor is the only cheap part, I would think the whole kabootle would be equally useless and cheap given it only works on a prius, which unless crashed usually never fails.

[cRiPpLe_rOoStEr]

Originally Posted by rmay635703

Also low end torque would not be an issue on a 2000lb van that originally came with a 2cycle engine (not much low end on a 2 cycle)

Which year is that van? I actually love 2-stroke engines...

[serialk11r]

Originally Posted by mr220v

The 1nzfe ecu runs the vvti based on rpm. I want to run it based on throttle position. With the setup I have, the vvti actually needs to operate more like displacement on demand than normal vvti. That's the object. Cruise at 750cc's, and move to 1.5L when I need to.

In the case of the spyder, the key would be the 1nz XA bellhousing accepting the spyder differential. I think it probably would. At that point, you would use your existing axles and transmission mounts.

That's not really how VVTi works. The stock ECU is doing about as good a job as it can, it should vary based on rpm and load together. High rpm => retarded intake cam for higher VE, high load + low rpm = advanced intake cam for more power, low load + low rpm = retarded intake cam for lower VE and lower pumping loss. Don't mess with it.

Yea I wouldn't be surprised if some of the 1NZ bellhousings worked, but I still have the exhaust piping to worry about afterwards. In California a custom exhaust isn't going to pass visual inspection for smog, even if the puny looking 1NZ doesn't raise an eyebrow

[mr220v]

On the low setting the motor is absolutely gutless. This is at all rpms. Pulls away from a light at a very leisurely pace. What you would expect from a 750cc mr2.

By contrast we ran a celica with a vvti 3mzfe. Vvti off had great low end but no high end power. With it on all the time it made good peak HP but nothing down low.

This was a California refed car running a 1mzfe non vvti ecu. The 1nz could probably make it past the ref too.

[Occasionally6]

Originally Posted by cRiPpLe_rOoStEr

That would demand some custom work to bolt everything, but it's not exactly impossible.

It's not that you couldn't bolt a manual trans. up but the way in which the power outputs of the electric motor and ICE are distributed depends on the trans.

[California98Civic]

I have a very basic question about this project that will reveal my inexperience but that would be helpful with my own longterm mod planning. How do you learn which engines and transmissions will mount easily in the engine bay? Do you judge from factory service manuals or do you have to get your hands on the engines first to compare? Is it just gradual accretion of knowledge through experience? How would I learn how adaptable a given engine is with a transmission? A given engine/trans combo in an engine bay? I do not want to distract the thread. I'm just really impressed with your fluency with these swap possibilities. THANKS!!

[rmay635703]

Originally Posted by cRiPpLe_rOoStEr

Which year is that van? I actually love 2-stroke engines...

The 2 cycle varient only came in Japan, everywhere else this is called a Perdua Kanari and has a 1ltr 4cycle motor

[vskid3]

Awesome project! A pipe-dream of mine is to swap a Prius or Camry Hybrid drivetrain into something like an MR2, or regular engine w/ manual tranny into a Prius. The Prius is great for economy, but has much to be desired in the acceleration department.

One question, how do you figure that the Atkinson valve timing makes it 750cc and 6:1 compression? I've never seen any numbers for the effective compression ratio and I just didn't expect it to be so extreme.

[Occasionally6]

Originally Posted by California98Civic

I have a very basic question about this project that will reveal my inexperience but that would be helpful with my own longterm mod planning. How do you learn which engines and transmissions will mount easily in the engine bay? Do you judge from factory service manuals or do you have to get your hands on the engines first to compare? Is it just gradual accretion of knowledge through experience? How would I learn how adaptable a given engine is with a transmission? A given engine/trans combo in an engine bay? I do not want to distract the thread. I'm just really impressed with your fluency with these swap possibilities. THANKS!!

Service manuals, parts books, wandering around junkyards and looking.

[Occasionally6]

Originally Posted by vskid3

One question, how do you figure that the Atkinson valve timing makes it 750cc and 6:1 compression? I've never seen any numbers for the effective compression ratio and I just didn't expect it to be so extreme.

The air/fuel charge is not trapped until the inlet valve closes. When that does occur, the volume of air/fuel trapped is that defined by the remainder of the stroke. Compression likewise does not occur until the inlet valve closes.