GM is going backward, the idiots

[Crazieboutamerc]

I was reading in the new issue of Off-road. About the "new" variable displacement engine in the mid siz suvs. It seems that GM is moving backwards trying out alread failed ideas.

Anyone remember the caddy with the V8-6-4 that did the same thing,:shake: never made it,

The "new" 4 wheel steering that jeep had in WWII, and honda had on the Prelude in the late 80's never went over.

And there new commercial opening roof, what's the point in that.

a 60k horse sub running silent DOH, nucular powered NOT diesel. then the 4 wheel steering. big whoop.

I think that GM is just tring to play catch up with ford.

Tim

[Directedby]

I think the new GM products are innovative and I am glad that they are at least trying to technologically improve their vehicles.

[TripleTransAm]

Originally posted by Crazieboutamerc
It seems that GM is moving backwards trying out alread failed ideas.


Well, 20 years does do a lot to automotive technology, you know. Microprocessors were operating on 1 MHz with a small 8k on board RAM in the early 80s? And now we have distributed control modules controlling various subsystems (PCM, BCM, AirBag, etc.)... just the PCM s/w on my LS1 supposedly sucks up 4 meg of space.

As for playing catch-up with Ford... judging by all the little glitches I've experienced with my car (popping rear, harness, squeaky seat, weak paint, dangling wire in trunk, seat cover undone, tire wear, etc...) I'd say I might have to look at GM once again if they ever get back into the fullsize RWD market. I really love the MM, but as far as trouble free motoring goes, my '98 Trans Am is miles ahead at the time of this writing.

(and since reading about the SOHC cam tensioners falling apart and contaminating the oil system earlier today on BON, I'm afraid to see what kind of corners they cut with the DOHC versions... I don't want to end up driving a glass motor ready to blow up and relying on some 'secret warranties' to cover my butt...)

[RCSignals]

TTA, I somehow suspect the SOHC tensioner thing involves very few engines.

[Jeff]

I can happily report 10550 miles of trouble-free motoring! :D

[JLHARVEY1]

With the ever increasing pressure from the EPA GM has two choices.... develop displacement on demand, or power it's full size trucks with 2.0 ltr 4 bangers. I applaud them on the decision to develop the displacement on demand. Caddy just tried to do it before we had the technology to do it right.

[Mad1]

Hey, don't be so down on them.

Sometimes an innovation is just ahead of its time and people aren't ready for it yet. Same thing happened with airbags ... they were considered a big "expensive" flop the first time they got put in a car. Now, they're practically standard in everything.

Mad1

[jaywish]

Hi Guys,

I'm guessing from the post that the displacement on demand is valve and spark controled like the old caddy's?

Just think, wouldn't it be nice to have a 500CUI V8 that drinks fuel like a 250 when you are just loafing?

Big blocks could be here again!!
:banana2:
Just a dream....?

[TripleTransAm]

Originally posted by jaywish
I'm guessing from the post that the displacement on demand is valve and spark controled like the old caddy's?


It's been about a year since I read GM's new proposal for displacement on demand so I don't know the specifics. I do know that it can't possibly be as bad as the first attempt.

If memory serves, the Caddy attempt involved dynamic rocker fulcrums that used to change the fulcrum point of the rocker arm from the center (allowing the valves to be rocked open by pushrod action) to the valve end, allowing the pushrod to push the entire rocker up while the valve stayed shut. With this system, there will be tons of pumping loss because it's still trying to compress *something* in the cylinder (probably some leftover exhaust gases), and I'm sure a mechanical valvetrain modification system using 70s tech couldn't have been all that smooth or efficient (imagine a Honda VTEC with vacuum lines to control the cam timing - yechhh...)

With modern electronics, it's childs play. Using electronically controlled lifters or cam followers, you just switch off the valves you don't want actuating, and keep the exhaust valves open. You can kill spark to those cylinders, and kill fuel altogether. With the right programming, all it takes is a slight flick on the pedal and you begin to get cylinders back on line.

I do believe I read something about a year ago touting m***ive displacements (in the low to mid 4xx cubic inches) for GM's new displacement on demand system.

[JLHARVEY1]

FYI

Mercedes has been using this technology for a few years now. I've heard nothing negative about it. They do not use it on thier supercharged or turbo engines though.

Speaking of fuel mileage, when the Marauder first came out, Ford claimed that they could've achieved more power but it would've put the Marauder in Gas Guzzler tax territory. How and Why would this happen?

GM's low tech LS1 and the older LT1 both achieved more power and better gas mileage from a larger engine using older technology. This confuses me. Maybe if Ford would bribe some of GM's powertrain engineers to come work for them :D

[LCpl Retired]

You missed one:


And there new commercial opening roof, what's the point in that.


1960 (ish) Studebaker "Wagonaire"

[Fourth Horseman]

Originally posted by TripleTransAm As for playing catch-up with Ford... judging by all the little glitches I've experienced with my car (popping rear, harness, squeaky seat, weak paint, dangling wire in trunk, seat cover undone, tire wear, etc...) I'd say I might have to look at GM once again if they ever get back into the fullsize RWD market.

Amen to that!