New Powertrains: I'm A Believer

[Chaz_23]

I'm also a fan of the 3.8, especially supercharged. One has to wonder what it would be capable of doing mated to the six-speed in terms of power and fuel efficiency. I don't think there's anything wrong with pushrods by themselves. I can't imagine anyone driving a SC 3.8 wishing for a DOHC.

[63GrandSport001]

after all of the people saying so many bad things about the 3400 and 3800 V-6 engines I drove vehicles with both engines expecting it to be a really bad experience.

I was shocked at how people have turned these engines into something worse then they really were. I compared it to some OHC motors that Ive driven and what I found was this. The 3800 V-6 compared to what the comp. is offering offers tons of low end torque which defies its low horsepower rating for the engine size. I can to this conclusion, the 3800 was tuned to best operate in the rpm range where most people drive which is idle to about 3,500 to maybe 4,000rpms on normal daily driving. They didnt care much about what the engine does at rpm levels higher then that. For this reason you had a motor that people ended up loving a lot and a engine that could pretty much smoke what even the Japanese were making from a stand still. The pulling power of even the 3400 at low rpms is pretty impressive, I drove a Chevy Nox with the lowly 3400 and my friend happens to own a 2005 Impala with that same engine in it.

My conclusion is the same as its always has been, most peoples perception of GMs OHV V-6s are omewhat off. You have to consider that the comp. is using more then 4 gears which effects fuel economy, performance, and shift quality. Go from a 4 speed to a 6 speed and it can be like night and day how the vehicle performs in that situation. People are also comparing engines that were designed and engineered just a few years ago to engines that were first designed and engineered in the 1970s.

[VivienM]

Originally Posted by Michael_S

Presumably the 6.2 will be available on lower trim level Silverado and Sierra pickups as part of the heavy tow package within a few years. The sooner the better.

But can GM do that and still manage to meet its CAFE requirements?

They better sell a big huge pile of Lambdas to make up for it...

[VivienM]

Originally Posted by 63GrandSport001

I can to this conclusion, the 3800 was tuned to best operate in the rpm range where most people drive which is idle to about 3,500 to maybe 4,000rpms on normal daily driving. They didnt care much about what the engine does at rpm levels higher then that.

The problem is that reviewers drive at 4000RPM to redline on a daily basis. And thus they give the 3800 lousy reviews...

[Ghrankenstein]

(howpeculiar) The 9-3 Aero with 6spd, and G6 GTP are the finalists at this point. We where VERY dissapointed with the CTS (the 5 speed automatic was terrible!), and you get a much better interior and transmission with the G6, for less money.

I'm really surprised at your experience with the 5L45E/5L50E CTS.

I adore the CTS, and I'll continue to butt-trumpet about how that car is made better by the automatics' PAS and PAL software.

Caddy has done a good job of acoustically tuning both HF engines, but the 2.8's improvement is especially noticeable. I also think that the 5L45E works particularly well with it; the 3600 lb 2.8L CTS is friendly and eager in the corners, to me at least. PAL is the clincher, which downshifts automatically (rather than upshifting) when lifting off the throttle, as long as the sport mode is engaged. For its modest power and torque ratings, it's surprisingly light on its feet, and entertaining to me.

I'd take a 2.8L automatic CTS with the 17" sport package over an equally priced 3.6, and I'd actually take the automatic over the stick with either engine. I think it's that much fun.

That's just my opinion; if more people shared it, this board would be crawling with members espousing the overwhelming need to devour human brains. So take it for what it's worth.

I'm curious to hear what you didn't like.

Ghrankenstein

[Michael_S]

Originally Posted by VivienM

But hey, it's not the MBAs' fault that they have pesky unions, manipulated currencies, and whatever other excuses they come up with to cover up the fact that the American MBA church-of-quarterly-results destroys companies like automakers...

It's the structure of the whole economy, though. If a particular leader doesn't squeeze the company for maximum short term profit instead of long term gain, the shareholders will replace him with someone else that will.

People like Warren Buffett (who makes billions of dollars by buying companies with long term plans and holding them until those plans are successful) are the exception, not the norm.

[SierraGS]

Originally Posted by Ming

Great write up, Ghank!

The main problem with the 3800 is simple and straighforward. GM stopped any real efforts at improving and keeping it competitive back when Clinton was in office.

Really, not much more needs to be said beyond that. If anyone thinks GM can survive by selling product it has put zero R&D effort into for years, they are living in a dream world, blinded by nostalgia.

The 3.6L is a great engine, and in the right applications it shines even in the fuel economy department. I recall that the weaker 3400 V6 actually got worse fuel economy in the Buick Rendezvous than the 27MPG/HWY 3.6LV6 version. But generally the 3.6L hasn't been known for delivering stellar fuel economy, and that worries me a bit in a time when gas mileage is more important than ever.

The E-85 capable 3500VVT interests me more for a commuter car, and the price is usually right. Difference with the "value" sibling 3800 is that the 3500VVT architecture actually has been updated and improved regularly for the last few years. While the 3800 horsepower has stayed the same, and even declined in the Lucerne to below 200hp, the 3.5LVVT V6 is up to 220+ hp. Just a few years and the 60-degree V6 (3400, 3500-preVVT, 3.5LVVT) has seen a 30+ hp jump from 185-odd hp.

If the 3.6L DOHC engine is set to replace the 3.5LVVT OHV engine, I sure hope that they add things like E-85 capability and tweak at least a car or two in GM's stable that the engine is put into for maximum fuel economy, even if that means losing a little get up & go.

The 3500VVT with E85 is a great engine that GM needs take advantage of the MPG and V6 Torque and install it into the HHR and Delta platform. This engine delivers great real world MPG and according to the EPA MPG website:


2007 Impala V6 26.7 MPG
2007 Accord V6 24.0 MPG
2007 Camry V6 23.2 MPG

The Malibu? 32.0 MPG

And the Impala and Malibu are thousands of dollars less.

The fact the 3800 has not been revised in years is GM's way of getting rid of it - too bad it still delivers good MPG and low Emissions.

What will replace it?

Either the 3900 with a boost in MPG or GM could develop a 3900 to 4500 LS2 V6 for the GMT900 and use it in the LaCrosse and Lucerne and possibly the Colorado. The approx $1,000 in savings over the 3.6L and the fact many LaCrosse and Lucurne buyers will be more than happy with it help.

The 3.6L with 270-300 HP should be the performance engine and be offered in the Impala LTZ and the Colorado - the Holden Rodeo uses it so it will fit.

The 3.2L version should be offered also, the 3.2L is better suited for the automatic trans. of the U.S. market than the 2.8L. The 2.8L Turbo is a good engine and best with a manual trans (though a 3.6L turbo would be better)

[SierraGS]

Originally Posted by VivienM

Have you compared the gearing between the 3.8 and the 3.9?

Let's see here... 3800/4T65-E always has a 3.05 or 2.86 final drive.

3.9L/4T65-E in Impala has a 3.29. In Malibu/G6 it's 3.69.

My guess is that that's what explains the MPG difference...

I always wondered why the 3900's MPG were disappointing - the 3.5 and 3500 have always done well. Wonder what a 6-speed with a taller 6th gear would do for MPG?

[VivienM]

Originally Posted by Michael_S

It's the structure of the whole economy, though. If a particular leader doesn't squeeze the company for maximum short term profit instead of long term gain, the shareholders will replace him with someone else that will.

Yup. Somehow I don't think they practice business like that in Toyota or Honda land...

Originally Posted by Michael_S

People like Warren Buffett (who makes billions of dollars by buying companies with long term plans and holding them until those plans are successful) are the exception, not the norm.

Warren Buffett has enough credibility that Wall Street analysts and everybody else don't pressure him to sacrifice long-term for short-term... and even then, everybody WAS laughing at him back in 2000 for having been a sucker who didn't buy into Internet stocks...

[pinyon]

My new Aura XR, while still breaking in, gets substantially lower MPG than my 2000 Grand Am GT with the 3.4L and 4sp auto and the Aura turns a few less RPM in 6th as apposed to the Grand Am at highway speeds. While the Aura is clearly a superior vehicle I always found the Grand Am GT to be a peppy driver that got good mileage even though it hardly handled like a "GT". Even though it was only rated a 5BHP higher than the standard model, I though it felt much stronger. My son's eagerly awaiting the hand me down on his imminent college graduation.

[63GrandSport001]

Originally Posted by VivienM

The problem is that reviewers drive at 4000RPM to redline on a daily basis. And thus they give the 3800 lousy reviews...

That is a very good point, my first drive in a 3800 V-6 I lined up with a VW Passet and I killed him off (two lanes merged into one).

"It's the structure of the whole economy, though. If a particular leader doesn't squeeze the company for maximum short term profit instead of long term gain, the shareholders will replace him with someone else that will."

I have to agree with this major problem that many American business men and America people seem to follow. They live from quarter to quarter and for that reason its hard to make a long term fix it plan in a American company because they will dump you after a few bad quarters in order to make their share holders happy.

" GM has a competitive truck engine, the 403 horsepower/417 pound feet 6.2 liter pushrod beast that's in the Sierra Denali, Yukon Denali, and Escalade.

The problem is, you can get the Toyota 5.7 liter engine in a $25,000 Tundra regular cab. The cheapest GM model with the 6.2 is a $38,000 Sierra Denali - and you can't even get the heavy towing package on the Sierra Denali.

Presumably the 6.2 will be available on lower trim level Silverado and Sierra pickups as part of the heavy tow package within a few years. The sooner the better."

From what I hear GM is working on revamping their Vortec line of SBC truck engines as well as bringing 6 speeds to the whole GMT-900 line. What I hear is in line for the Vortec engines is they will all get VVT and direct injection which will put what everyone else has in production to shame. Not to mention that they will get 6 speed autos mated to them so dont be shocked if Toyota gets its ass completely handed to them.

The only problem is we have to wait for these new engine and transmission to come out as GM is making major moves in every market in the world right now.

From what I have heard VVT gives a 10% boost in power and something like a 5% boost in fuel economy and GDI gives a 15% boost in power and 5% boost in fuel economy. So I will try to est. what these engines will be making based on what the current engines make.

4.3L V-6
240BHP
290ft-lbs

4.8L V-8
340BHP
360ft-lbs

5.3L V-8
370BHP
400ft-lbs

6.0L V-6
410BHP
425ft-lbs

mated to 6 speed manuals and these engines can also get something like 15% better fuel economy then they get right now.

[SierraGS]

Originally Posted by 63GrandSport001

That is a very good point, my first drive in a 3800 V-6 I lined up with a VW Passet and I killed him off (two lanes merged into one).

From what I have heard VVT gives a 10% boost in power and something like a 5% boost in fuel economy and GDI gives a 15% boost in power and 5% boost in fuel economy. So I will try to est. what these engines will be making based on what the current engines make.

4.3L V-6
240BHP
290ft-lbs

4.8L V-8
340BHP
360ft-lbs

5.3L V-8
370BHP
400ft-lbs

6.0L V-6
410BHP
425ft-lbs

mated to 6 speed manuals and these engines can also get something like 15% better fuel economy then they get right now.

I thought the 4.3L was going to be replaced by a LS2 derivative in the 3.9L to 4.5L area. This would make sense with more component sharing (rods, pistons, valves, VVT hardware, water pumps etc.) with better heads and a stronger bottom end.

A LS2 4.3L should be approx 280 - 300 HP and 320 - 330 ft-lbs.

Another choice would be a 4.5L version of the 4.2 (if the same increase from the 2.8-2.9 and 3.5-3.7 were done to it). This would give GM a class exclusive I-6 that many truck buyers like and give one of GM's best engines a proper home. GM should add GDI and tune it for torque with maybe 300 HP and 325 ft-lbs this would increase MPG with a 6-speed since it could hold the higher gear.

They could make a V-12 out of it for HD trucks and the Sixteen.

[VivienM]

Originally Posted by SierraGS

Another choice would be a 4.5L version of the 4.2 (if the same increase from the 2.8-2.9 and 3.5-3.7 were done to it). This would give GM a class exclusive I-6 that many truck buyers like and give one of GM's best engines a proper home. It would be in the 300 - 320 HP range but GM should and DI and tune it for torque with maybe 300 HP and 325 ft-lbs.

But... is it really wise to use the more expensive-to-build engine as the base engine? (Mind you, GM beancounters are probably capable of doing something that dumb...)

[Michael_S]

Originally Posted by 63GrandSport001

From what I hear GM is working on revamping their Vortec line of SBC truck engines as well as bringing 6 speeds to the whole GMT-900 line. What I hear is in line for the Vortec engines is they will all get VVT and direct injection which will put what everyone else has in production to shame. Not to mention that they will get 6 speed autos mated to them so dont be shocked if Toyota gets its ass completely handed to them.

The only problem is we have to wait for these new engine and transmission to come out as GM is making major moves in every market in the world right now.

From what I have heard VVT gives a 10% boost in power and something like a 5% boost in fuel economy and GDI gives a 15% boost in power and 5% boost in fuel economy. So I will try to est. what these engines will be making based on what the current engines make.

4.3L V-6
240BHP
290ft-lbs

4.8L V-8
340BHP
360ft-lbs

5.3L V-8
370BHP
400ft-lbs

6.0L V-6
410BHP
425ft-lbs

mated to 6 speed manuals and these engines can also get something like 15% better fuel economy then they get right now.

I hope you're right, but for the moment this is all complete speculation.

[red_rider]

Originally Posted by bcjohnso99

Really?

2007 Camry (3.5l/268hp) 22/31
2007 Accord (3.0l/244hp) 21/30
2007 Impala (3.9l/233hp) 20/29

OHV = Lowest hp, worst fuel economy (not a leader in torque either)

what does peak hp have to do with fuel economy? You don't run at 6k rpms while you're getting these mpg numbers, a comparison of low-end power (torque ratings) and mpg would be a more valid comparison.