I passed on the Prius mainly because I did not find the driving position to be comfortable, but also, I did not like its small size and lacking engine. If the larger TCH had a smaller engine, I might not have bought it.

Also a smaller engine in the Hybrid might not result in much better fuel economy. Keep in mind that the 4cyl Camry gets about 1 MPG better than the V6 Camry.

 

Consumer Guide Auto shows the 2008 Camry epa mileage at..

3.5, 6-cyl mpg 19/28

2.4, 4-cyl mpg 21/31

2.4, hybrid mpg 33/34

 

ekpolk — I agree with some of the comments made by others; namely, that the TCH ICE's power is designed to give it comparable acceleration to the regular V6. But you are quite correct that, had Toyota chosen to use a smaller ICE in the TCH, it would have gotten even better fuel economy, at the expense of acceleration. Would this have been a better marketing choice? I personally doubt it. The Prius fills that niche.

By the way, ignoring the acceleration issue, only a relatively small amount of ICE power is needed to allow steady-state cruising on level roads. The closer the ICE's power rating is to the needed power, the more efficient it will be in general. Over-sizing the ICE for better acceleration and hill climbing actually lowers its efficiency at the fractional power demand of steady-state cruising. The TCH's ICE does have an offset crankshaft (like the Prius' ICE) in order to reduce frictional losses during the power stroke. You are quite correct that it's the longer expansion stroke in the Atkinson/Miller-cycle ICE design that is mainly responsible for its greater fuel efficiency — more of the heat energy is being extracted from the hot gases. The expansion ratio is around 12.5:1, but because of the delayed closure of the intake valves, the effective compression ratio is more like 10:1, which is why it can use regular gasoline. This means that, from a fuel consumption point of view, it behaves more like a regular 1.8-liter engine.

Stan

 

According to Consumer Reports, they tested the overall fuel efficiency of the hybrid, 4cyl LE, and V6 XLE as 34, 23, & 24, respectively.

 

Stan:

Good comments. I spent the last 2+ years learning the Prius, its quirks, strengths, techniques, and so forth, only to sell the car to my son and get a TCH. Back to the bottom of the learning curve! Question: are you positive that the 2AZ-FXE has the offset crankshaft? Another hybrid "expert" told me it did not. Not a biggie either way, of course, I just like learning the car.

For everyone, I didn't start this thread to criticize the car at all. Again, I love mine -- much more comfortable and solid feeling than the Prius. What I'm finding is that the TCH, and I assume mine is working toward the end of break-in, and my techniques are adapting, is settling in to a pattern in which under any given conditions, it gets about 10 mpg, give or take a little, less than the Prius would have. And this is the genesis of my question. The TCH weighs between 600-700 lbs more than a Prius, so adjusted for weight, the cars are probably roughly equally as efficient. That got me wondering how much benefit might have been had with the smaller ICE. Could a TCH, tweaked appropriately close the gap between itself and a 600 lb lighter Prius?

Oh, and another factor that comes into play: I'm by no means one of these hard-core Type-B guys who thrives on crawling along like a snail. Believe it or not, I drove a G35 before the Prius. One of the "problems" I'm confronting as I break myself in to the TCH is quelling the temptation to get on the gas hard and enjoy the blast of go. Something of a "pent up demand" problem as the economists might call it.

Anyway, the more the merrier as to comments on the TCH power/overpower thing. Quite honestly, I don't know if I'd have taken a TCH if its performance was on par with the I-4 either. One could certainly argue that the I-4 is waaaaaay cheaper up front, so what would the TCH then offer? But it's certainly a good car as it, and again, I'm lovin' it, and not complaining.

 

Gene and all,

Interesting question, and one for which there may be no "right" answer. Generally, I agree with Stan that the Prius fills the "all out economy" niche. (Well, perhaps not all out; Toyota certainly could make a car with even better FE, but it might be akin to a motorized skateboard.....).

The Camry is positioned as a a traditional five-passenger sedan, and the TCH sits in the middle of the Camry lineup in terms of performance. That seems reasonable.

Personally, I wouldn't be surprised to see more options, perhaps including an engine option, over the next few years. Right now, Toyota has little reason to offer extensive options, as they still are tapping the early adopter market. Going forward, though, as hybrid technology becomes mainstream, that may change. Meanwhile, I really don't think that the TCH is in danger of falling into the Accord Hybrid trap: my understanding is that the Accord Hybrid mileage was hardly better than the Accord 4-cylinder model, while the TCH published city mileage is over 50% better than the 4-cylinder Camry SE's. And, in my experience, the published mileage for the TCH is way lower than what is routinely achievable.

 

IMHO, yes, I probably would have PASSED on the TCH if it only had 4-cyl performance. My last few cars have all been 200+HP V-6's. Performance is still important to me. I'm not racing, but when I need to get onto the highway and step on the throttle, I want it to MOVE!

 

Keep in mind what was going on when the car's fundamentals were being finalized back in 2003-2004 time frame: power was king, and faster was better. The TCH 'final spec' was no later than 3Q 2005. So, given the cost premium, Toyota figured the 'more power' would be an easier sale. Also, one of the issues with hybrids during extended periods of power demand (like climbing a 5+ mile grade) is that the battery runs out of ability to provide boost, thus leaving you with whatever the ICE can provide. A smaller engine, especially coupled with altitude power loss, would make the car unsellable in a fair number of markets.

Now, if Toyota figured a way of losing 400+ pounds of weight without too much cost bloat, and went with a Direct Injection setup, and maybe put the variable cam magic on both the intake and exhaust cams, the 1.8 could provide the needed power, while giving a notable improvement in FE. Maybe for the next generation.

Interestingly enough, the '10 Prius is going with a bit bigger motor, with a claimed improvement in FE. Likely all the development on the inverters and batteries is contributing, but goes to prove small displacement is not necessarily the best way to good FE.

 

I'd have bought the TCH with a smaller engine, but after over 2 years of driving I feel a less powerful engine would have been marginal. I do appreciate and am happy with the 2.4L engine. It climbs 6 and 7% freeway grades without excessive revving or complaints, and "B" safely holds the speed down under 70mph while going down those grades.

I've owned a number of vehicles that had "marginal" power. Forget even trying to pass on a hill with either of these two below.

My '82 VW Vanagon Diesel makes anything else seems zippy!! For those who never had the pleasure, it developed 48HP and pushed close to 5,000 lbs down the road. I'd have to say the 0 to 60 times often exceeded 1 minute. If you had over a 10 mph head wind, forget about ever seeing the plus side of 60mph. The plus side was it averaged a bit over 30 mpg no matter how it was driven.

Another powerhouse I had was a '71 Honda 600 Sedan. The 600 was powered by a mighty 0.6 liter 2 cylinder air cooled engine. It was a bit quicker, 0-60 in about 20 seconds.

 

Interesting comments; thanks everyone. Nash, one of the funniest cases I've ever had in a courtroom was a DUI in which my guy had been driving a 1968 VW Microbus. He was leaving Pensacola Beach, and a busybody with a cellphone got irritated with him for some reason, called 911 and accused him of being drunk (long story, but I'm satisfied he was not). Anyway she told the cop, and testified at trial in front of the jury, that my guy was doing at least 80 mph going up the Bob Sykes bridge (for those unfamiliar with the area, it's the main bridge to the beach and crosses the Intercoastal -- pretty steep on both sides -- shipping clearance). Anyway, the jury was openly laughing during closing argument when I suggested that a 68 VW Microbus couldn't go 80 mph DOWN the backside of the bridge with a shuttle rocket booster strapped to its roof, in full burn. We got an acquittal with less than five minutes of deliberation. Go figure.