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Report: Cadillac to offer Duramax V8 diesel in CTS?

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Old Oct 16, 2008 | 09:19 AM
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Report: Cadillac to offer Duramax V8 diesel in CTS?

http://www.leftlanenews.com/report-c...el-in-cts.html

I like the idea

Originally designed to propel SUVs and pickup trucks, GM’s 4.5-liter Duramax V8 turbodiesel powerplant could find its way under the hood of the Cadillac CTS. The idea is unusual, but perhaps not a controversial as the prospect of a four-cylinder Caddy. If a new report is to believed, GM is strongly considering the possibility.

The Duramax mill delivers 310 horsepower, and, as diesels do, a massive amount of torque — 520 pound-feet to be exact. Critically, GM says the engine meets emissions standards in all 50 states.

The engine might serve to fill the gap between the 304 horsepower V6 and 556 horsepower “V” in the CTS range, according to Motor Trend, but we think it would have to be up-tuned to around 420 horsepower to accomplish that goal.

While shoehorning a diesel into a Cadillac is a bit of a risk from a marketing point of view, the technical feasibility of such a move is very favorable, and the cost to GM would be minimal. The CTS is already capable of fitting the engine without issue, and a suitable transmission is readily available.
Old Oct 16, 2008 | 09:25 AM
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I like it, maybe a diesel Camaro next.
Old Oct 16, 2008 | 10:51 AM
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What kind of fuel economy figures would we expect to see? If it's not making 30+mpg highway, don't bother.

The E320 diesel gets 32mpg hwy granted it only makes 210hp/400lb-ft tq. Maybe they should detune the 4.5L duramax. I think most people would be willing to sacrifice a bit of hp/tq for an increase in fuel economy. I don't think the CTS diesel needs 310hp and 520lb-ft of tq. 250hp and 440lb-ft of tq would suffice.
Old Oct 16, 2008 | 11:20 AM
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Originally Posted by Gold_Rush
What kind of fuel economy figures would we expect to see? If it's not making 30+mpg highway, don't bother.
I agree, if it can't get great mileage (30+) and be faster than the V6 (nonDI) then don't bother.
Old Oct 16, 2008 | 12:03 PM
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Did they completely kill the idea to put it in half-ton Trucks and SUVs?

How much does the 4.5L weigh compared to the 3.6 or LS8 (or is it LSA)?
Old Oct 16, 2008 | 03:51 PM
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GM doesnt have the ***** to do this I think it would be sick to see a duramax in a CTS . It would be rather simple for the end user to make it faster than a CTS-V
Old Oct 16, 2008 | 05:05 PM
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Originally Posted by My Red 93Z-28
How much does the 4.5L weigh compared to the 3.6 or LS8 (or is it LSA)?
My understanding is that its LSX sized, but I'm not sure if that's the weight or just the dimensions.
Old Oct 16, 2008 | 06:21 PM
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The engine might serve to fill the gap between the 304 horsepower V6 and 556 horsepower “V” in the CTS range, according to Motor Trend, but we think it would have to be up-tuned to around 420 horsepower to accomplish that goal.
420 horsepower, huh? Doesn't GM already have an engine that makes right at that? The naturally aspirated 6.2L V8 makes between 380-436hp in current vehicles. Naturally, that would fit perfectly between the V6 and the Supercharged version.

Originally Posted by Gold_Rush
What kind of fuel economy figures would we expect to see? If it's not making 30+mpg highway, don't bother.

The E320 diesel gets 32mpg hwy granted it only makes 210hp/400lb-ft tq. Maybe they should detune the 4.5L duramax. I think most people would be willing to sacrifice a bit of hp/tq for an increase in fuel economy. I don't think the CTS diesel needs 310hp and 520lb-ft of tq. 250hp and 440lb-ft of tq would suffice.
Compared to the 2.9L V6 version, the 4.5L V8 is detuned.
V6 = 86.2 hp/L & 140.0 ft-lbs/L
V8 = 68.9 hp/L & 115.6 ft-lbs/L

The V8 tuned to the same specific output as the V6 would make 388hp & 630 ft-lbs!

Last edited by AdioSS; Oct 16, 2008 at 07:01 PM.
Old Oct 16, 2008 | 07:02 PM
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The engine might serve to fill the gap between the 304 horsepower V6 and 556 horsepower “V” in the CTS range, according to Motor Trend, but we think it would have to be up-tuned to around 420 horsepower to accomplish that goal.
They obviously don't understand diesels. 420hp? Are they crazy? Considering diesels don't rev very high it would be making around 700lb-ft to make that kind of power. Drivetrain capacity is determined by torque and the 4.5 is perfect right where it is to be mated to CTS-V components.

Last edited by ImportedRoomate; Oct 16, 2008 at 07:10 PM.
Old Oct 16, 2008 | 09:00 PM
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No kidding...it'll have the enough torque to pull a damn trailer behind it

Leave the engine as it is. Diesels can be modded fairly easy, let the owner take that step if he/she desires.
Old Oct 17, 2008 | 08:14 AM
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Is it just me or does MT not have a clue about how diesels operate. 520 lb/tq is enough to snap your head clean off in a Caddy package. Mated with a 6 speed this this would crush that V6.

Last edited by soul strife; Oct 17, 2008 at 10:30 AM.
Old Oct 17, 2008 | 10:21 AM
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Exactly. Not only that, it'll be making that torque almost from idle.
Old Oct 17, 2008 | 11:39 AM
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Gearing would have to be completely different then the gas models.

2.73 gears and that thing would just MURDER. Sounds *** backwards.
Old Oct 21, 2008 | 10:35 AM
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As usual for GM, its overkill. The 4.5L motor would probably add 250lbs over the front tires of the car. I know its graphite iron blah blah blah, you still have the weight of the turbo, intercooler, oil cooler, piping etc. The handling would be **** poor and you dont need 520ftlbs, the 2.9L would be perfect in this application and stilll provide 400ftlbs and could manage 35mpg. Contary to that author's thinking you DONT need to fill the gap between 300hp and 550hp. Plus they'll turn around and complain about the NVH of a truck motor in a Cadilliac.
Old Oct 21, 2008 | 11:34 AM
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Originally Posted by Flip94ta
As usual for GM, its overkill. The 4.5L motor would probably add 250lbs over the front tires of the car. I know its graphite iron blah blah blah, you still have the weight of the turbo, intercooler, oil cooler, piping etc. The handling would be **** poor and you dont need 520ftlbs, the 2.9L would be perfect in this application and stilll provide 400ftlbs and could manage 35mpg. Contary to that author's thinking you DONT need to fill the gap between 300hp and 550hp. Plus they'll turn around and complain about the NVH of a truck motor in a Cadilliac.
Compared to the CTS-V? Both have the "supercharger" on top between the cylinder heads. Either diesel will need the 6L90E and the heavy duty rear end from the V.

Why do you think the new diesel is a "truck engine"? Because there has been mention of putting it in half-ton trucks? There was also talk of putting it into the full-size RWD Impala.

I think the CTS could use a V6 diesel tuned to the same specific output as the V8. It would make right at 200hp/335tq with the potential for over 35mpg.



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