Chevy & GMC have been featuring displacement on demand technology on their full size SUVs claiming gas milage improvement of up to 20%. As I understand it, some cylinders shut down under light load, such as in OD, and hence provide better fuel economy. Is this mod as good as they say and would such a feature be compatable with the V10?

 

Welcome to the site!

There have been a few discussions on this subject in the past. Even one guy trying to build his own DOD system if I remember correctly. Might try searching or look back several 'pages' in this forum for some of those threads.

The way many of us drive, I don't think DOD would ever be a viable savings feature.

 

FORD should be looking into this too! Not just for the V10...but also the for the 5.4 and 4.6. Heck for all it's gas engines...

I know Honda has done this with its Odyssey V6 for 2005 and 06. The technology is available (computer management systems) and should be used...IMHO.

FORD are you listening???

biz

 

ford uses it already in the cooling system on these engines. if it overheats it shuts cylinders down so ford can do it but when is the question?

 

Didn't GM have this option in the '80's in their caddys? If I remember right they could cut back from 8 to 6 to 4 cyl depending on the load. It was a total failure and the mechanics disconnected that feature.

If you want to save fuel, then get off the cruise control, and use your right foot as a fuel shut off valve, shutting down the fuel to all the cylinders-----you may not desire the results from fuel shut off.

 

chevy has had a lot of failures remember the small block 350 diesel. what a joke. those barely drove off the assembly line.

 

Yep, and people really have some screwed up thinking when they say this GM DOD system is the answer to fuel economy. He-ll, if most folks would just slow down, maintain proper tire inflation, and stop unnecessary engine idling their fuel mileage would go up instantly without all this DOD crap. I hope Ford stays away from it!

 

The key is "up to". Check out the latest issue of Car & Driver for an article by one of their editors on how the fuel milage numbers you see on the window sticker are calculated. It's a process developed in the sixties and not even remotely close to people's driving habits. However, GM and DC can get "up to 20%" better numbers on this unrealistic measuring stick by needlessly complicating the engine.
Honda's setup on the other hand is sweet. Built they stand with a more aerodynamic vehicle (less drag) that sits closer to the ground. Plus Honda's engine was desogned from the ground up to incorperate these features, not adding them on as GM & DC is doing. Reminds me of a certain V8-6-4 from my youth............

 

Reminds me of a certain V8-6-4 from my youth............



which one?do tell.

 

Cadillac! Talk about un-inspired design.

 

They make terrific motorcycles. I should know, I own 3 of em (ooops, forgot, the ex took one in the D settlement) They are fairly priced, and excell on reliability and power. I do like my HONDA motorcycles.

On the other hand, I had a HONDA car once...Yeah, DOHC 16 valve 4 cyl motor, a real screamer until one afternoon the OHC belt slipped a notch and bent all 16 valves! 55k miles...Very expensive valve job. Then I started having expensive front end repairs...Never will I have another one.

 

DoD systems might have merit on a vehicle that normally gets 25mph or more but on trucks down in the 10-13mpg range what would be the point of all the added complexity just to get a 10% average benefit only 20%30% of the time?

Even if the system could give you the advertised "up to 20%" improved economy that relates to an extra 2 or 3 mpg... whoopee! I can get that just by accelerating a little slower, airing up the tires, adding a bed cover, and driving like a senior citizen every where.

Like a few of the fellows above I too hope and pray Ford passes and never plans anything like DoD on the modular series motors or control computers... OBDII is already complicated enough!

My vote is for the hydraulic accumulator hybrid motor adaption. Storing energy during braking and then releasing it back to the rear wheels during acceleration is a great idea and not very complicated. Not too sure how you would adapt it to a 4x4 vehicle so you don't have a large variance between front and rear power levels.

 

sorry guys but it aint about us, it's about the CAFE numbers, they get tougher every year, and it's about advertising to draw folks into the showrooms. In a computer simulation the mileage increases with DOD, so the automakers get to raise the Corporate Average Fuel Economy numbers and prevent huge penalties. The Prius is rated over 60 mpg, so the 4.7 liter Tundra's can still get 11 mpg and deliver huge profits for Toyota. Real life economy for the Prius is 30-40 mpg, but Toyota gets to use the EPA estimation for CAFE.

 

Ken04 of course is absolutely correct

It is all really a shell game and once again the consumer gets caught in the middle of EPA, vs Government, vs Manufactures in the loop hole and hype wars!

Funny how we keep electing complete idiots to govern us... he said shaking his head

 

I'm still waiting for the testing to be complete on the Hydrogen conversion kits that are currently under development. They are also working on hydrogen injection that will work on any vehicle, fuel injected or carbeurated. Supposed to give up to an extra 25% in mpg.


Tony