Fuel Smart - Aftermarket cylinder deactivation module?

[BIRDMAN]

This seems very interesting - however I cannot find much information on it. This leads me to believe that this is too good to be true? This module claims to retrofit a variable displacement system in any fuel injected vehicle.

You would think this would be a big deal if it were true.

Fuel Smart Corp. - About Us.

 

[KaiserM715]

GM uses collapsible lifters (deactivated via a solenoid) in addition to programming to do this. Net gain is about 10-20% fuel economy improvement. I think 25% is really overselling this. I don't know anything about this company. I would do a LOT more research before I would ever think of installing it.

 

[Hockster]

One of the first systems was Gm's caddie... think it was a 84.. called 4,6,8... it shut down cylinders when you didnt need them. didnt work very good at all... but i cant see why it wont work... its so east to shut off fuel now... best way for this is to be able open the valves so there is no compression...

 

[Ruger]

Hockster has it right about the Cadillac 4,6,8. A failure.

I think I disagree on holding the valves open. I think that the pistons would force whatever is in the cylinders back into the intake manifold. That would certainly booger up the flow in the manifold, may even stall the flow in the manifold, and would certainly change the fuel to air ratio of the intake gasses that enter the active cylindrs.

 

[BigJ]

I ran an MDS (multi displacement system) engine for 2 years before dumping it (2005 Hemi). 10% mpg gains is an overstatement; its 10% while it engaged, which is only when cruising under no load. How much actual no load cruising you do? Its probably a lot let than you think. Bottom line for me was it was a marketing and EPA appeasement effort that has very little to do with the real world.

As for the tech... I wonder what this does to the ECU itself. I mean, as far as the O2 sensor is concerned, your engine is running lean now right? You've got 4 cyl worth of fuel being burned instead of the 8 its used to seeing, everything else being equal? So does that mean the ECU will richen up the mix dumping more fuel into the cyls that are still "on"? Meaning you end up burning at least as much gas as before, if not more?

Or how about misfire codes? What about the knock sensors?

Sure is starting to smell like snake oil around here...

 

[KaiserM715]

GM uses collapsible lifters (deactivated via a solenoid) in addition to programming to do this.

One of the first systems was Gm's caddie... think it was a 84.. called 4,6,8... it shut down cylinders when you didnt need them. didnt work very good at all...

Hockster has it right about the Cadillac 4,6,8. A failure.

The system I am talking about is in my G8. It is not a bad system, but cannot tolerate any sort of aggressive cam due to the lifters. Not even close to the same animal as the 4,6,8, which was such a dismal failure that GM disabled it on almost of the cars after the fact.

I think I disagree on holding the valves open. I think that the pistons would force whatever is in the cylinders back into the intake manifold. That would certainly booger up the flow in the manifold, may even stall the flow in the manifold, and would certainly change the fuel to air ratio of the intake gasses that enter the active cylindrs.

+1.

 

[WHYUMAD]

Ogle Vapor Fuel system....when will they mass produce this.

 

[Hockster]

I ran an MDS (multi displacement system) engine for 2 years before dumping it (2005 Hemi). 10% mpg gains is an overstatement; its 10% while it engaged, which is only when cruising under no load. How much actual no load cruising you do? Its probably a lot let than you think. Bottom line for me was it was a marketing and EPA appeasement effort that has very little to do with the real world.

As for the tech... I wonder what this does to the ECU itself. I mean, as far as the O2 sensor is concerned, your engine is running lean now right? You've got 4 cyl worth of fuel being burned instead of the 8 its used to seeing, everything else being equal? So does that mean the ECU will richen up the mix dumping more fuel into the cyls that are still "on"? Meaning you end up burning at least as much gas as before, if not more?

Or how about misfire codes? What about the knock sensors?

Sure is starting to smell like snake oil around here...

THe 02 sensors do not tell the PCM to increase or lean out the system. They are a set of eyes that inform the PCM if the system is running rick or lean, if it sees a problem it sets a code thats all... things that determine fuel mixture are the ACT, ECT throttle position and air flow... But, Im sure that it would interfere with things since the strategy is set by the factory and its more than adding a interface from this company. Shit, if it was that easy the aout manufactures would have now since its claim is a high % MPG increase

 

[BigJ]

^^Hmm I hear ya... maybe its different with the Ford programming, but I've seen the Chrysler PCM code and raw tables, and if I recall correctly the O2 sensor information does factor into the decision making process.

 

[Steele16]

On my Mach 1 the 02 sensors absolutely affect the fuel mixture. So much so that when I had a collector leak on the drivers side in front of the sensor it was dumping enough fuel to that bank to foul the plugs on that side only.