CVT vs Manual for economy

JimIsbell · 10-08-2008, 11:21 AM

I found this on http://www.waterfuelconverters.com/ while doing research on those snake oil people.

"CVT transmissions allow the engine to remain at a particular RPM, while providing acceleration by constantly varying gear ratios. Since the efficiency of the engine varies by RPM the most efficient region can be targeted for longer periods of operation. By forcing the engine to operate for longer periods of time, in an efficient RPM region, fuel economy is effected."

While this seems to make sense, it would seem that the lower efficiency of the CVT negates any gain if the lower mileage on the CVT Insight is any indication.

Any comments?

**uhtrinity** · 10-08-2008, 01:14 PM

CVT Insights don't do lean burn, so it is an apple / orange comparison. I would bet a properly tuned CVT in an Insight with lean burn could put out some great mpg numbers.

JimIsbell · 10-08-2008, 02:29 PM

I wonder how difficult it would be to do that because the CVTs are cheaper to acquire than the manuals.

joecvt · 10-08-2008, 03:24 PM

Besides lack of lean burn, CVTs engines output less horsepower and torque. CVT Insights also weigh more. However, besides the comfort of not having to shift gears, CVTs are certified for much better emissions than its MT brother (enough difference to fall into a better category of emissions: SULEV for the CVT, ULEV for the MT)

It would be very difficult (if not impossible) to convert a US model CVT to lean burn due to different ECM, catalytic converter, fuel and emmission lines from engine to gas tank, etc The MT ECM, if swapped out, would not provide communication to the TCM (Transmission Control Module) like required on the CVT model. I guess you could try and get all of the parts needed from a Japanese model CVT with lean burn but then there may be problems with emission certification.

JoeCVT = Just your average CVT owner