Does anyone know why Honda hasn't incorporated VCM in all their non-hybrid V6 vehicles? It seems to me that it would be easy and inexpensive to add this feature to all their V6's -- 3 cylinders would provide ample power when cruising at steady speeds. The gain in fuel economy would be significant and the complexity(and cost) of adding an electric motor avoided.

 

Comparing the Odysseys the price does seem to be very small. The difference in the price between the EX and EX-L is only $2300 and there is more of a difference than just the VCM. The gas mileage difference is 1 MPG in the city and 3 MPG on the highway. It does look fairly inexpensive to implement. Maybe they just want to test it some more.

Billy

 

The problem you have is that without an electric motor, your acceleration would suffer while switching from 3 cylinder mode to 6 cylinder mode.

It is better on a hybrid, because the electric motor can kick in with extra power while the cylinders are coming back online.

Electric power is instantaneous.

But, I know that other companies have tried VCMs in the past without much success.

 

I'm sorry, did you say 1 MPG city/3 MPG highway improvement with the VCM Odyssey? How is that really an improvement? I would think keeping your tires inflated would help just as much. Just wondering.

 

Finman:
Well... 3 mpg is OVER a 10% gain - over 50 miles per tank more. And having VCM does not preclude the ability to increase PSI in your tires. However, the ride and handling is so incredible in our Odyssey, I'll forego the harsher ride of the higher PSI.

Blueskies:
There is no hesitation switching from 3 to 6 to 3. There is NO evidence of the change whatsoever. It is an awesome engine.

I predict it will become more prevelant in the other v6 models.

 

But is that with the Accord Hybrid? You have an electric boost there right? Have you tried it with a non-hybrid car? Or can you disable the assist and try it without?

 

Blueskies,
Check out my signature. Listed is an '05 Odyssey EX-L - that has the VCM. My wife drives it, except on trips when I drive.

 

VCM may not be that cheap to add on. The assymetry of using 3 cylinders causes engine vibrations that have to be dealt with by adding stabilizers and dampening. So there is cost, and weight.

An otto engine is efficient around 50% of max power output; so in the case of the over-powered Odyssey, even 3 cylinders is too much at highway cruising speeds. Without a hybrid configuration, the engine must operate at a low rpm, inefficient power range.

Perhaps an 8 cylinder, 15 bhp/cylinder configuration would do better.

 

The VCM drops to 4 cylinder then to 3. You see an indicator ECO, on the instrumant panel, which indicates the drop to 4 cylinders, then if the cruise is steadty and a very flat surface the engine will sometimes drop to
3 cylinders. It is constantly switching from 4 to 3 cylinders and adjusting electric moter mount to obsorb the shock. In ECO mode you will be useing
4 cylinder more often than 3. When the engine drops to three there is a very low vibration that is canceled out by the ANC, and you see an drop in the rpms that really confusses some drivers. It is a very nice system and the designer needs a pat on the back with this system due the fact it remains within the LEV standards!!

 

The reason the hybrid does use VCM is due to the fact that the hybrid uses the IMA motor as a generator to charge the battery. When braking the IMA motor is energized as a generator. The magnetics also assit in slowing the vehicle. The would interfere the the VCM cylinder drop or pause.