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danielgr
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Well, this weekend and for the first time we had both the Fit and CR-Z in exactly the same trip following each other. The result (corrected based on lifetime BC figures inaccuracy) ??
- CR-Z 6MT : 20.8 km/L or 48.9 mpg
- Fit L13 CVT : 18.9 km/L or 44.5 mpg
That was a 10% advantage for the Z !
Some key specs of our cars:
- CR-Z 6MT alfa (with Navi) : 1.5L + IMA, 1130kg (2491lbs), 124Hp, 174Nm (129 lb-ft), and 195/55R16 alloy wheels
- Fit 1.3G CVT (with skyroof & Navi) : 1.3L, 1070kg (2360lbs), 100Hp, 126Nm (93 lb-ft), and 175/65R15 steel wheels.
Now, based on cumulated mileage over similar itineraries I had already concluded long ago than my CR-Z more than fulfilled my initial aspiration of "considerably more performance with better FE than our 1.3L CVT Fit", but it is the first time I get a direct comparison.
Here are the details of the trip. Basically we refueled at the same gas station, followed each other to the millimeter until the destination. CR-Z always lead the convoy, with cruise control set at 101kmph (63mph) on the freeways, and both cars using A/C for the whole trip on the already scorching Japanese summer (auto in CR-Z with ECON mode, and manual A/C on the Fit). Both cars with only one passenger, and most luggage (though not much) on the CR-Z.
And here the "proof of FE" shots (two different ones for the Fit since it cannot display the FE and trip distance on the same display, both taken within a few seconds and GPS tagged...)
Last edited by danielgr on 07-16-2012 11:10
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IntegraDC5R
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I need to have some weight reduction surgery done to my right foot. :) With the final drive change to a 4.68 from the stock 4.29 and my heavy foot, I'm only seeing like 9~10km/l in daily running, and on the expressways I only get about 13km/l, mostly because I can not drive just 100km/h, I tend to start falling asleep from boredom. hahaha
Nice comparison Daniel between the 2 vehicles, even better that the CR-Z is beating down the 1.3 Fit.
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Fan Koni
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Nice details - thanks.
Have you read any comparisons on the Fit 1.5 hybrid MT in Japan? Would like to know if Honda upgraded the system somehow from the CRZ for the Fit.
Maybe wishful thinking, but if Honda invested some into it then it may get exported.
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danielgr
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Fan Koni wrote:
Nice details - thanks.
Have you read any comparisons on the Fit 1.5 hybrid MT in Japan? Would like to know if Honda upgraded the system somehow from the CRZ for the Fit.
Maybe wishful thinking, but if Honda invested some into it then it may get exported.
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Afaik, nothing invested on Fit Hybrid RS other than adapting CR-Z's drivetrain to the Fit.
Last edited by danielgr on 07-17-2012 02:16
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Restless
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hmmmm
Given that big part of the trip was constant speed, perhaps we can attribute the advantage to MT vs CVT?
IMA impact shouldn't be so big?
Also:
- maybe bigger engine is better suited for going up (more torque, and perhaps IMA helped?)
- CR-Z is heavier and had wider&bigger tyres. I remember Insideline.com had compared acceleration&mpg of Golf 6 with different tyres, 1 inch bigger tyres were found to be worse for fuel economy and also, every inch was 0.1s slower speeding to 100km/h
So CRZ was at disadvantage in the comparison! With same tyre size mpg difference will be bigger.
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danielgr
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Restless wrote:
hmmmm
Given that big part of the trip was constant speed, perhaps we can attribute the advantage to MT vs CVT?
IMA impact shouldn't be so big?
Also:
- maybe bigger engine is better suited for going up (more torque, and perhaps IMA helped?)
- CR-Z is heavier and had wider&bigger tyres. I remember Insideline.com had compared acceleration&mpg of Golf 6 with different tyres, 1 inch bigger tyres were found to be worse for fuel economy and also, every inch was 0.1s slower speeding to 100km/h
So CRZ was at disadvantage in the comparison! With same tyre size mpg difference will be bigger.
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The point with the CVTs is that when driven on low loads (as we did) they enjoy major benefits over MTs in terms of gear ratio span. I can already see it when comparing the CR-Z with the Fit, whenever I'm on flat or slightly downhill terrain, the Fit instant FE metter shows better FE than the MT CR-Z, simply because despite it's theoretical higher loses it's at running 1000 or more rpm less. To beat that I'd need a 7th gear on the Z !!!
IMHO where the CR-Z makes the difference is 100% on IMA, and outside the city it comes with every elevation change. The fact is that graph may seem rather flat at some areas, but that's only because the GPS app is averaging values. In most Japanese roads "flat" is a very rough approximation, and what you have is constant up-down hills, which may not be very high, but are everywhere. Indeed, even at constant speed IMA is working it's ass off nearly all the time, and it did so on this particular trip. That is specially noticeable on an MT car, because IMA allows you to go up most slopes on 6th gear whereas typically a 1.5L NA engine would require you to downshift in order to keep it at speed (and your FE would get a serious drop because of it). Conversely, the tiny motor with super-low friction oil allows recovering most energy when going down and cruising (because it has very low friction compared with larger engines).
So sure the CVT gets the advantage of having the "perfect gear for each slope", but the CR-Z compensates by having "the perfect motor assist" for each one.
Both gasoline CVT and IMA MT suffer more than regular MT non-hybrid cars when driven faster (at constant speed). On the CVT case because the transmission is forced to use shorter gearing to keep speed, losing it's "wide-ratio advantage". On the MT IMA because with higher speed there is more friction and less for IMA to charge; as a result you start running out of juice in most slopes when going up, and your milage starts dropping like hell (that is also why rain has such an impact on hybrids mileage... rain = much greater friction). There is really a sweet spot (speed) where you have each time just enough battery to go up, then charge before the next one !
That said, personally I see it differently, it's not that IMA MT / nonhybrid CVT cars lose more at speed, is that they reward your gentle driving much more than other cars !!! And yes, many times it makes you drive slower, simply because you know FE will get so much better...
Finally, I think that on a summer day (like this one) the ability of ECON to handle the A/C provides a non negligible advantage over the manual A/C in the Fit as well. In the Fit you can usually clearly see the FE impact of A/C, whereas in the CR-Z sometimes it's pretty hard to tell if it's making a difference at all on it. At least me, I tend to have the best FE on summer, even better than during spring-autumn...
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danielgr
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IntegraDC5R wrote:
I need to have some weight reduction surgery done to my right foot. :) With the final drive change to a 4.68 from the stock 4.29 and my heavy foot, I'm only seeing like 9~10km/l in daily running, and on the expressways I only get about 13km/l, mostly because I can not drive just 100km/h, I tend to start falling asleep from boredom. hahaha
Nice comparison Daniel between the 2 vehicles, even better that the CR-Z is beating down the 1.3 Fit.
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Otherwise, I personally also find it very hard (border line impossible) to stay at 100 unless I'm using the cruise control, and when I drive the Fit I tend to go faster...
The thing is:
1) Cruise control only works up to 110km/h in Japanese Hondas.
2) As mentioned in another thread, there is a noticeable hit when driving at 110km/h instead of 101km/h, whereas in terms of time it makes really little or no difference (even over 650km...).
3) When driving at 110km/h you risk being caught if you happen to inadvertedly do it on one of the many freeway portions with a 80km/h limit.
So basically unless I'm on a rush, I tend to drive 101 or 105km/h, because:
- Freeways are boring no matter how fast I go (unless we enter European territory at about 200km/h, and still, it depends on the road...)
- Using cruise control removes 90% of my driving fatigue, makes me win time by stopping less.
- I get amazing FE
- I don't have to worry about speed limits, 'cause I know police will never stop me at those speeds no matter what.
Then again, I never go into a freeway "for fun" ... :P
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IntegraDC5R
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Wanted the better acceleration when out on circuit, it coupled with the LSD makes it a very fun, but still slow vehicle in the grand scheme.
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WongKN
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As usual, daniel did a near perfect job explaining the relative merits of the CVT vs a 6MT and also the advantage of the IMA. I just want to add two thoughts/feedbacks for the discussion.
1. The CVT's greatest advantage is that it has a seamless gear range. In practise, this means that it often runs at a gear ratio way taller than one of the gearboxes with discrete gears, even a 6MT. However, this advantage applies up to only a limit max speed. In my experience, the max speed one can run with a CVT when going for max FE is around 80-90kph. Of course I understand to drive on the highway at this speed is simply not possible for lots of TOV/TOVA'ers. But the fact is that once going above that speed, into the '3-figures' territory (100kph and above), the CVT loses the gear ratio advantage esp to a well designed 6MT. So the CVT and the 6MT in 6th gear will run the engine at similar rpms. In this case, the extra advantage of the IMA now gives the edge over to the CR-Z.
2. The advantage of the IMA over the CVT over -real- roads is significant. Even highway or freeway roads which as Daniel rightly points out are never really truly 'flat' in the sense that there will usually be uphill and downhill portion. In this case, when we enforce a fixed speed like 101 or 105kph which Daniel did, the advantage really goes to the IMA because of the assist over uphill portions. With a CVT only, with IMA, my experience is that one needs to put in a lot of 'work' in order to fully exploit it over real roads. E.g. what I do is I modulate the throttle on the uphill just enough such that the engine spins at lowest possible rpm, even if the car is slowing down, but at a balance point such that it slows down to an 'acceptable' speed right at the top of the hill. Then I use the downhill portions and again put as little pressure as possible on the throttle so as to get the engine out of 'closed throttle' operation. The idea is to remove 'engine braking' but yet use as little fuel as possible. In this instance, the car will pick up speed and I try to let it pick up as much speed as possible (subject to safety conditions of course) so that I have more speed to 'give away' on the uphill climb.
E.g. there is a highway called the 'MEX' in Malaysia which has a long series of alternating up and downhill stretches, over 30km long. So I will be picking up speed, say up to as high as 120 or 130kph on the downhill, and then allow the Jazz to lose speed on the uphill. With experience, I can time it such that the Jazz loses 40-50kph on the uphill, ending up at 70 or 80kph right at the top and just nice for the next downhill segment. The cycle then repeats. I can maintain engine rpm at or below 2,000rpm all the way with minimum throttle, just a light tap on the throttle. And I can get close to 20km/l on a good day, when there are no traffic hindering my routine. Of course I stay on the leftmost lane (slowest lane) - remembering that we are RHD over here and drives on the left side of the road.
When we enforce a fixed speed, such as when using the auto-cruise at 105kph for e.g., what happens is the CVT will push up the gear ratio and apply throttle in order to maintain the speed at 105kph and then apply the brakes on the downhill portion. So we get -exactly- the situation where the IMA is to exploit - i.e. we use up energy to maintain speed at the uphill and then 'throw' it away by braking on the downhill. The IMA in this case, recovers part of the wasted energy on the downhill by charging and storing it in the battery and then re-uses it, -recycling the energy in a sense- by assisting the engine on the uphill, easing the demand on fuel usage.
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