I read an article about GM making a V8 engine that can turn off four cylinders for better gas mileage, What a great idea, those ricers would really hate us then, what could they say when our engines make more power yet get the same mileage. Is this concept pretty far off, like years and years down the road, or could they possibly introduce something like this in say the 5th gen F-body

 

I think its called displacement on demand, and a lot of other imported cars are already getting it or are about to.

1) If they can get it to work right, then I would plan on seeing it in our cars in the next few years...as for the 5th Gen Camaro, no one knows if theres going to be one yet so we don't know if it will have displacement on demand.

 

I'm pretty sure a 3.6L v6 motor like this is going in next years Malibu.

 

Something like that was tried in a Cadillac a few years ago. Miserable outcome.

 

Yeah, that's why I'm a little sketchy about GM doing this. But that was in the 80s, or something like that. The computers and technology now are far more superior today, so I guess that's why GM has higher hopes for it working.

I really hope DOD will work, and not have a lot of nagging problems that will kill it.

 

yeah right, them you'll have a bunch of "rice patties" roll up to you and roll down their window, "hey, lets race, turn off 4 cylinders"...i once heard some one say (an accord to a mustang) i'll race you if you pull 2 spark plugs, i never thought the same way of that guy

 

It's coming next year in GM's pickup trucks, and will most likely find its way on the C6. I'd be willing to be it will show up on almost all future high-performance OHV V8s

As to the comments comparing it to the V8-6-4 Sevilles, please, that was 20 years ago. It's like saying I don't want a computer in my home today because I had a Commodore VIC-20 in 1981 and it was useless. Time to move on and update your opinions!

 

Amen...GM has come a long way from the V8-6-4....

 

WowI thought I was the only one with the commodore vic 20, that thing was pretty lame, i think mine sat in the box most of the time, except for the rare moments I played the free games it came with, which sucked too!

 

Should show up on 2004 5.3 pickup engines. Improves city milage by around 8%, and highway milage by 25%.

GM's "Displacement-On-Demand" uses hydraulic lifters that can be collapsed, to turn off 2 cylinders on each bank. The result is a even-firing V-4. The '80's Cadillac V8-6-4 was a very crude attempt, using mechanical linkages from the throttle and transmission to control the deactivation of the cylinders valvetrain.

The new D.O.D. uses sensors and the PCM to decide when to shut off 4 cylinders. A demonstration for the press a while back proved the system to be seamless - the driver was unable to determine when the engine was in V8 vs. V4 mode. Plus, the engine always STARTS and IDLES in V-8 mode for smoothness, and predictable acceleration from a stop, then switches to V4 only when cruising with low load. In limp-home mode, the system remains in V8. Todays PCM processor is more than adequate to handle this type of control routine. The only additional cost is for a set of specialized lifters, and a relatively simple hydraulic circuit. Very cheap for a pushrod V8. More expensive/complicated/bulky for OHC.

Ford and Chrysler are playing catch-up to GM with this technology, and it's one of the reasons Chrysler abandoned their 5.7 OHC engine development in favor of the Hemi pushrod engine.

Adding this feature to GM's Trucks and Sport Utilities will have the greatest effect on lowering their CAFE, so expect to see it first there, then later show up on other vehicles (Vette?, 5th Gen?, etc.)

 

PGR, you just summed up something that made me laugh out loud thinking about a conversation I had with a friend once (not laugh at you, what you said was great and accurate). I made a comment about Ford and their switching from the 5.0 windsor to the new OHC 4.6 and how it was a mistake. My friend starts in with how OHC is the wave of the future, it makes better horsepower, cheaper to make for modular, and some other stuff. I looked at him funny and asked a few pointed questions (such as GMs LS1-derived modular pushrod engines, didn't seem to have an answer for that though) and he made the final comment about how OHC can meet emissions restrictions when pushrods won't be able to. I asked him about DoD developements and he said it wasn't feasible due to cost, requirements, ect. I really like the fact that GM decided to prove that the good "old tech" pushrod isn't the dinosaur some of these people have been saying it was. For me, there was never any doubt. Now if GM can take some of this and make me a new 5th gen that is a Camaro, I will be truly happy with them again.