"Keep in mind..."

Yet if the 4cyl in the standard Camry used the Atkinson cycle it would probably get 50% better FE than the V6. The secret for the hybrid would be to use a small SuperCharged I4 that could produce the HP/Torque of the current I4 under "hard" throttle.

That would mean using a combination of the Atkinson cycle and the Miller cycle. Use the Atkinson cycle for low torque highly efficient FE and then transition into miller cycle mode for high torque, acceleration, requirements.

In Atkinson cycle mode the positive displacement SC would just "loaf" along producing only enough intake flow (no throttle plate) for the needs of the moment. Put your foot into it and the lightweight (carbon fiber) SC quickly spools up to provide BOOST while at the same time the intake valve closing delay transitions to give an effective cylinder compression ratio of 8:1.

"Hard" cylinder compression ratio of ~16:1 with overall effective ratio of 12:1 (DFI) in Atkinson cycle mode.

ICE driven SC via a Prius type CVT with a wide range variable speed synchronous AC motor for the other CVT input.

 

I'm happy with the Atkinson 2.4/L ICE in my TCH. It has plenty of power, unless your talking about V8 acceleration, i mean. It also gives plenty of mpg for it's size. It's a great car with a seemless CVT that seems to do the job very well.

 

I would have also passed on this car if it only had V4 performance. I test drove the Prius when I was still deciding which car I wanted and it was so sluggish. I wasn't about to sacrifice performance for gas mileage. The TCH was exactly what I wanted.

 

Yes, but in the other direction

I'd have gone with a variable cylinder (2/3-4-6) V6. Running only to charge the battery would only use 2 or 3 cylinders. Normal to hard acceleration & cruising would run on 4. Max acceleration kicks in all 6. All of these would be tied into the PSD like the current system w/ an EV mode button and a dashboard indicator of which mode the V6 is in.

 

Honda tried that in the Accord Hybrid. Result was considerably worse FE than the TCH. Granted, there are considerable differences between Toyota's and Honda's hybrid approach, but the Accord hybrid resulted in a relatively expensive car with very good acceleration, but so-so FE. And very few sales, which may have a part of the strategy - get the systems perfected and manufacturing costs down on low-volume, high-margin models.

 

Frodo:

It's a tantalizing possibility. Personally, I think that Honda's "hybrid strategy" is substantially inferior to the one Toyota uses (but again, that's my opinion), and their decision to use a V-6 in the Accord was that car's death knell. The closest thing Toyota has is the 3MZ-FXE, found in the Highlander Hybrid, which produces an average mpg of about 27 for most users. How this driveline would have worked in the TCH is anyone's guess. Plenty less vehicle to haul around, but six cylinders to feed. Again, I think I would have gone the other direction (that is, smaller ICE), but again, I still really love this car. I just seriously miss the occasional tank average topping 50 mpg which the Prius would give me.

 

I don't think the Accord had the electric motor assist to the engine once the car was over 35 mph. I'm guessing at the speed. That's where toyota found extra mpg, by assisting the engine in the hybrid mode at cruising speeds.

The Honda Civic hybrid may be set up more like the Toyota hybrids are now.

 

I would have been happy with a smaller engine, but the MPG is already so high I'm not sure it would be worth the savings.

For what it's worth, our TCH has more horsepower than any car I've ever purchased and I've purchased 12 over the past 40 years. 4 were V-6's with less power and the rest were 4's. None of the 4's had over 100 HP. And I got along just fine.

 

Honda has a strong "NIH mania", where their key technologies have to be designed 'in-house'. Witness their "unique" approach to automatics, whereby no Honda-manufactured vehicle has ever had a planetary automatic. The design has had some advantages, and it has kept Honda from paying licensing fees.

Honda's IMA approach certainly has the KISS approach advantage, and is somewhat lighter than the Toyota's HSD. I'd suppose it's more a matter of different sets of compromises - typical of every engineering solution. The experience of the Honda board members is that the Civic Hybrid has better highway FE, whereas the Prius has somewhat better city FE, where the full parallel approach pays dividends. I wouldn't call either design bad, but each has a different sets of weaknesses.

And Honda (like any other manufacturer) tried to create a new niche for a 'performance hybrid'. As sales figures have shown, that market niche was quite limited. I looked at the Accord Hybrid, and found it a very nice unit, but at a 'you've got to be kidding' price point. The nominal price was roughly $3K over an Accord V6, but the 'greedy weasel factor' at the dealers made the street-level difference over $5K. And the car offered neither a performance or a FE advantage to justify the premium.

 

My thoughts exactly.

An to the OP's point about Honda, I think that comparison is more accurate for Lexus than for the TCH. The engines paired with the HSD in the Lexus' make the fuel savings negligible. It id purely a performance booster (more total HP) and the conscience-saving "h" badge with the model number (IMO). I looked at the Lexus GS hybrid and just couldn't make the math work from a savings standpoint. It's a beautiful/powerful car, but not so much more than the regular GS