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Can GM make Cadillac the standard of the world Again?

6098 messages,  Last post on Aug 14, 2009 at 4:43 PM

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What is this discussion about? Cadillac Escalade, Cadillac XLR, Cadillac STS, Automotive News


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#3463 of 6098
Re: First Drive: 2008 Cadillac CTS [rayainsw] by bumpy
Jul 31, 2007 (6:55 am)
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Replying to: rayainsw (Jul 31, 2007 6:29 am)

That looks like it.
#3464 of 6098
Re: First Drive: 2008 Cadillac CTS [bumpy] by plekto
Jul 31, 2007 (9:02 am)
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Replying to: bumpy (Jul 31, 2007 6:55 am)

There's a huge difference, though, between 2200-2400rpm and 1200-1600rpm in actual use.
 
Remember, despite it having all the power in the world, unless you can get a 6 speed manual gearbox with tight gearing in that "sports sedan" and then keep it in second gear around town(to get it into the 2500-4000rpm range - expect 16-18mpg!), you're stuck with loafing around town.
(of course *I* ignore gas mileage and do this - get about 250 miles per tank. 90% of people don't)
 
Mash the pedal - 3-4 seconds - 35-40 mph... torque converter locks up and you... "loaf". It shifts up a gear... you loaf. You want to unlock that torque converter and pass someone? Well, it's "loafing" at a whopping 900-1200rpm and you suffer a 2-3 second lag before it gets into its power band. The GM? Nope - none of that WOT-lag beahvior with this.
 
The BMW is an exception obviously because they use I-6 engines, which develop better torque and power for their displacement.(technically, the I-6 is the closest thing to a perfect engine that's possible from a power, weight, and efficiency standpoint - which is why BMW refuses to change)
 
P.S.
Though, you'll note that only TWO of the GM 3.6 applications are geared for low-end torque. The rest are no different from the standard stuff out there.
 
Go drive a CTS with the 3.6. Now, go across the street to the Buick dealer and drive the LaCrosse CXS. Same engine, same suspension, but which one drives better? Surprizing, isn't it? The CTS feels average. The CXS feels like a small block V8 from the 60s. Blip the throttle even a tiny but over idle and presto - maximum torque.
 
The new DI CTS seems to be simmilar - just without sacrificing HP to do it.
#3465 of 6098
Re: First Drive: 2008 Cadillac CTS [plekto] by bumpy
Jul 31, 2007 (9:34 am)
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Replying to: plekto (Jul 31, 2007 9:02 am)

There's a huge difference, though, between 2200-2400rpm and 1200-1600rpm in actual use.
 
Who would want to drive at 1200-1600 rpm?
 
As for the rest of it, it sounds like a torque converter is a death sentence for a good engine and a good reason to avoid the slushbox. Now, where's that manual Lacrosse?
#3466 of 6098
Re: First Drive: 2008 Cadillac CTS [bumpy] by plekto
Jul 31, 2007 (9:53 am)
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Replying to: bumpy (Jul 31, 2007 9:34 am)

Oh dear lord I wish GM made a LaCrosse with a manual...
#3467 of 6098
Re: First Drive: 2008 Cadillac CTS [bumpy] by rayainsw
Jul 31, 2007 (10:04 am)
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Replying to: bumpy (Jul 31, 2007 9:34 am)

“Who would want to drive at 1200-1600 rpm?”
 
Me, for 1.
 
My Corvette, in sixth gear shows 1600 RPM at approx. 73 MPH. A cruising speed I often find comfortable. Returning 30+ MPG. 80 MPH is approx. 1750 RPM.
 
But who’s counting . . .
 
- Ray
Happy at low RPM, cruising & happy at high RPM accelerating ( um ) briskly . . .
#3468 of 6098
Re: First Drive: 2008 Cadillac CTS [rayainsw] by bumpy
Jul 31, 2007 (10:20 am)
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Replying to: rayainsw (Jul 31, 2007 10:04 am)

Oh, a pushrod sure. They should have a little graphic of Mister Scott pop up on the HUD saying "She'll fly apart, cap'n!" every time the tach goes above 3500 rpm.
 
But who would want to run a DOHC V6 that slowly? That's like asking a thoroughbred to do a mule's job.
#3469 of 6098
Re: First Drive: 2008 Cadillac CTS [bumpy] by british_rover
Jul 31, 2007 (10:25 am)
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Replying to: bumpy (Jul 31, 2007 10:20 am)

That might be true of most pushrod engines but the new vette motors are not one of them.
#3470 of 6098
Re: First Drive: 2008 Cadillac CTS [bumpy] by sls002
Jul 31, 2007 (3:22 pm)
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Replying to: bumpy (Jul 31, 2007 10:20 am)

My SRX V8 with six speed slush box cruises 70 MPH with the engine running at about 1800 RPMs. It does kick down on up hills to 5th with the engine bumping up to 2200 or so. I averaged about 21 MPG on a long trip (it is still new though).
#3471 of 6098
perceptions by sls002
Aug 05, 2007 (8:43 am)
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Consider the following: take a pushrod engine - lets say this one:
http://media.gm.com/us/powertrain/en/product_services/2008/HPT%20Library/HVV6/20- - - 08_39L_LZG_Impala.pdf
Would re-engineering the valve train to have a DOHC instead of the single cam in block change anything? What I mean is to keep the two valve per cylinder design, with the same intake manifold and the same valve timing. I think below 6000 RPM's there would be no change in performance, torque or horsepower. Above 6000 RPM's the DOHC might possibly have bit more power, but with the peak horsepower at 5600 RPMs, it is more a question of falling off more slowly, not resulting in more horsepower.
 
The point of course is that with a DOHC design, one would have 4 valve per cylinder and separate VVT on the intake and exhaust valves. Then one gets something like this:
http://media.gm.com/us/powertrain/en/product_services/2008/HPT%20Library/HFV6/20- - 08_36L_LY7_CTS.pdf
 
The big difference between these two engines is the extra valves with the intake and exhaust timing variation independant of each other. The pushrods are irrelavant, except that they probably make putting more than two valves per cylinder difficult or of little real value.
#3472 of 6098
P.I.T.A.! by lemko
Aug 06, 2007 (9:10 am)
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I just noticed one of the license plate lamps was out on my 2002 Seville STS last night as I was putting it away. To replace this tiny 194 bulb one has to remove the fabric lining from the decklid, unfasten at least eight wing nuts and remove the entire taillamp cluster spanning the width of the decklid. Whatever happened to the days of simply removing a lens with a phillips screwdriver to access the bulbs? An unexperienced person would've given up and taken the car to the dealer at unnecessary expense to replace a bulb or ended up breaking the cluster which must be very expensive to replace.

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