Ok i remember along time ago i read about a concept car made by cadillac where they had a V8 except it was capable of shutting down 2 cylinders so it had a better MPG does anyone have any information to how this works? and if it could be done?

 

Only thing I heard about that was a Caddy V12 that shut down half the engine. Got the gas mileage of a V8.

I don't think a control system exist to shut down the cylinders. Even if it did, it would take a long long long time to pay for itself.

 

i looked it up on google cadillac made a system called 8-6-4 it was actually made and produced in cadilac cars

 

ya, but the 8-6-4 was a huge failure and didn't produce very good results

 

And that's why it's not still going today

 

interesting

 

This what I was speaking of...
http://www.cadillac.com/cadillacjsp/...jsp?model=cien

 

Some more....
http://www.gminsidenews.com/xv12.htm

 

my uncles got an 81 Caddy (was my grandfathers but he died :-() with that engine and i'm sure if i asked i could probably get it :-D haha

 

Actually GM made 2 new "adjustible displacement" engines, well prototypes anyway, I read about them in car craft. Ill go through my box and try to find it, but apperantly the v-6 (shut off feul/air/spark to one row of cylanders) worked flawlessly while the v8 (shut off feul/air/spark to the front 4 cyl.) was a little quirky. Both showed a lot of potential however, and may actually become reality in the near future. the concept is to shut off half the cylanders at idle and very low throttle (under 2k rpm I beleive) to improve city mileage.

 

the reason why that caddy engine didnt take off was it just didnt have a processor powerful enough to handle the system. Right now gm has a pretty large "variable displacement" research project going. Their concept was to simply use solonoids attached to the valve that activate it, that way you could simply kill any cylinder any time you wanted. Also you'd have infinite valve timing.

About two years ago they figured that it would come into production in 2005. That's not looking like a strong possibilty at this point.

This project was actually an off shoot of another project that involved making 1 single frame for all of gm's platforms. 1 frame for all cars and trucks. Not only was it a frame, but also a mobile electronics platform, one of the main features they hyped was the the body mounts were actually the electrical connectors to the from the frame to the body. I can't recall the name of the project, it had some kind of snappy name like "automotion" or something.

For all i know now that whole project is ditched. As with just about anything GM does these days, it seemed way too ambitious.

 

The one platform project is still ongoing kinda, I seen it on a car show as a "side platter" to the main course...The ONE BILLION DOLLAR CAR. Yes, a hydrogen powered POS. Wtf is this

 

That "pancake" platform is not only alive and well, but GM has three working prototypes. The latest variant operates on a hydrogen fuel cell, and has the potential to smoke any gasoline engined vehicle being produced today.

There was even a prototype showcased on an episode of CBS's "60 Minutes" several months ago. The oil companies are rightfully "very interested" in the development of the platform, and the prudent ones are already investigating the production and distribution of liquid hydrogen through their existing production and delivery networks.

For those who care to search outside the "normal" automotive world, there are already annual races of electric powered cars between engineering teams, and the best ones are already faster than most street cars. Anyone that works with or around brushless DC and AC servomotors already knows the immense torque and high RPM power potential of the motors. The power band and RPM limits make a Wankel engine look like a slug in a mud hole, and rival some lower speed (geared) gas turbines and jet engines. Kollmorgen and Relaiance Electric already build 60HP brushless DC and AC servomotors that weigh less than 100 pounds, can function as a driving and regenerative braking device, and can briefly produce and sustain 600% of their rated normal torque output at 0 RPM. The rated peak RPM is slightly over 10,000. Imagine 360 HP available at each of the four wheels for short bursts. How would you like to have the ability to smoke all four wheels with a pedal punch while travelling at 70 MPH? And all with no more noise than the shredding of rubber on the pavement and annoying shrill of thyristors oscillating to pruduce the high current/low voltage necessary to make the power. You electric lift truck and golf cart operators are already accustomed to the whine, albiet without the rubber burning.

GM itself is already very schooleed in heavy duty traction motors. All of their diesel locomotives are no more than a big diesel/electric generator set with a large traction motor at every drive wheel. No gearboxes, no driveshafts, and no more transmission other than semiconductor switching banks and big wires. They have been building them that way for over 50 years. GM Coach has used the same system for some over-the-road passenger busses.

The big stumbling block for the concept is the power source. Batteries can produce and deliver energy for only a fixed time period, but can deliver short bursts of very high current if desinged properly (like a starting battery). Their major drawbacks are their mass, and the ability to recharge them. A hydrogen fuel cell can slowly maintain a charge, and let the batteries sustain the extra load for short periods of peak operation. Diesel/electric sumbarines got along on that type of system for decades.

Another beauty is that the vehicles are truly multi-fuel, in that for short periods and brief commutes, one could operate solely on the battery, and recharge from a fixed point (like your garage) rather than burn hydrogen to recharge the battery. An owner could choose to either pay the hydrogen company or the electric utility that serves his area.

Battery and hydrogen fuel cell technologies will need to be advanced and refined before it's an econmoical, reliable, and effective solution, but it's coming.

 

Oh, yeah. I forgot:

http://www.azcentral.com/class/marke...hy-wire06.html