Wards Ten Best Engines For 2008

[poncho1982]

What cracks me up, is that the Ford 4.6L made the list.

[goblue]

This list has degenerated into a sea of placation. Notice how practically every automaker has something? What the heck is the old ford mod motor doing here. That POS has been due for replacement the second it came out. (Yes - I've driven it - its fine, nothing special) They could at least try to differentiate between the 4 cyl turbos - but no, they leave one of the best off the list and put up the rest.

[Michael_S]

Originally Posted by blank disk

Good point, I don't get the award for the 6.0L either. Nothing special in the engine, just the transmission.

How many hybrid Tahoes does GM expect to sell anyway? You have to spend thousands to save $600/year. That does not seem right to me, to spend that much cash to move from 16mpg avg to 20mpg avg for a 4WD. And the more hwy you drive, the less the benefit, as it is mostly gained in city driving.

If you read the rest of the discussion thread, you would note that the GM 6.0 in the hybrids is one of the few Atkinson (technically Atkinson-Miller) cycle engines on the road.

[E. Haskell]

Originally Posted by big swede

I think the LS3 and the turbo ecotec might have gotten left off because they are just too new and not many people have experienced them.

The 6.0 Hybrid isn't even on the market yet!

[vncj96]

Chevy knows how to build a V8 we know that probably no other better one out there IMO. But i have been very impressed with the DI motor and the more that will come out. and the design of the SC 6.2 coming out. A long way considering ten years ago they were still building that pile of a motor 3.4DOHC

[MelvinJ]

Originally Posted by mkaresh

Is the 332 for the engine alone, or the engine plus the hybrid motors? Other hybrid sellers have gone both ways. For example, the engine in the Highlander Hybrid is rated at 268 horsepower with the electric motor, and 209 without it.

The 332 seems low enough to be without including the electric motors, but somewhere recently I read that this figure includes the output of the electric motors. Which could be wrong.

Any idea?

GM doesn't quote figures for ICE + electric assist. Those figures are for the 6.0L by itself. http://media.gm.com/us/powertrain/en..._LFA_Tahoe.pdf

Originally Posted by Michael_S

Thanks for the example. But I-Love-Pontiac was asking why the Atkinson is not used in more non-hybrids. I was responding that I don't know. If it really does boost efficiency, why not replace GM's 2.4 liter Ecotec with a 3.0 liter Atkinson V6 that gets the same 169 horsepower but 15% better mileage?

In another thread, someone suggested that Atkinson totally ruins low end torque, and so it's only usable in hybrids where an electric engine can make up for the gasoline engine's weak low RPM power. I don't remember who said it... Xenon, maybe? But either way, it was just a guess and neither he nor I know for sure why the Atkinson cycle is so rare in modern engines.

I've read that the low-end torque really drops too, but on the linked graph for the LFA 6.0L, it's not much behind the L76 6.0L on the low end. It has more of an effect on the upper end, so I'm not sure what the deal is. It would be interesting to see the LFA tested in an otherwise conventional Tahoe to see if it would better the 5.3L. I can't see where there would add virtually any cost adding LIVC to an engine. It's just a different cam grind, right?

http://media.gm.com/us/powertrain/en...lanche_SAE.pdf

[Michael_S]

Originally Posted by MelvinJ

I've read that the low-end torque really drops too, but on the linked graph for the LFA 6.0L, it's not much behind the L76 6.0L on the low end. It has more of an effect on the upper end, so I'm not sure what the deal is. It would be interesting to see the LFA tested in an otherwise conventional Tahoe to see if it would better the 5.3L. I can't see where there would add virtually any cost adding LIVC to an engine. It's just a different cam grind, right?

http://media.gm.com/us/powertrain/en...lanche_SAE.pdf

Yes, I don't get it either. If the technology really doesn't kill low end torque, why not replace all of the 4.8s and 5.3s with Atkinson-Miller 6.0 engines?

[Chaz_23]

The Honda V6 is SOHC?!? I didn't think any of the high tech foreigners made SOHCs anymore.

[Michael_S]

Originally Posted by Chaz_23

The Honda V6 is SOHC?!? I didn't think any of the high tech foreigners made SOHCs anymore.

I'm pretty sure Honda's only DOHC engines in the US are the 2.0 liter 4-cylinders in the Civic SI and S2000. Everything else is SOHC - but it's 4-valves per cylinder SOHC.

[blaksabb]

Originally Posted by poncho1982

What cracks me up, is that the Ford 4.6L made the list.

I was thinking the same thing. What a POS motor. The power density is garbage and the aural qualities are nasty. There is nothing technologically sophisticated about it. The now defunct LS1 has much better breathing characteristics as a pushrod. What's Ward's AW thinking w/ this one?

[ogg vorbis]

Originally Posted by E. Haskell

Where is the LS3??

Road and Track recently compared the LS3 to V8s from the Aston Martin Vantage, Ferrari F430 and Audi R8....and it WON!

that's because the ls3 actually puts out 460+ bhp, 455+ lb-ft. the other 3 manage 302, 347, and 317 lb-ft, respectively. and it doesn't have to rev past 6500 rpm to do it. they got owned by a pushrod motor

[ogg vorbis]

Originally Posted by Michael_S

Yes, I don't get it either. If the technology really doesn't kill low end torque, why not replace all of the 4.8s and 5.3s with Atkinson-Miller 6.0 engines?

atkinson is great. the sidi turbo runs mild atkinson. in fact, the sidi turbo uses a lambda sensor - not a narrow band O2 - because it's pumping air straight into the exhaust. long duration reduces pumping loses, and is great for high rpm power. sidi works with long duration to eliminate pumping gas into the exhaust, and stabilizing idle.

on a side note: my buick regal needs a constant changed in the pcm to use E85. a lambda sensor sets optimum afr regardless of fuel composition. i.e. you can dump E85 in a solstice gxp, turn up the boost (preferably a larger turbo), and it's happy.

the problem with hanging the intake valve open too long is the air/fuel mixture is pumped back into the intake. sidi is pumping just air, so it works perfectly with atkinson.

[Beau]

Its not a mild atkinson at all.
Delaying intake valve from closing is not a mild atkinson cycle at all.

In this particular fashion for the SIDI motor, or any dual funtion VVT DI Turbo motor, will delay the intake valve from closing in order to enhance spool.

But yes also, the O2 sensor is considerd a wideband as with any MED9 based ECU.

And no, you cannot just dump in E85 into a Solstice GXP. The engine is calibrated to run at 12.5:1 under full enrichment, and runs around 15.0 and higher during no boost crusing.

I think Alcohol with DI, requires a STOICH of about 10.5:1. So it would need to run at about 8.5:1 under enrichment to maintain the same A/F ratio.

So, no, on top of not having the appropriate seals for the E85, the tables also would not be fueling it properly. Don't go telling people their GXP SOL is E85 compatible.

[Lawnchair8]

Originally Posted by AMcA

And it oughta get a lot more use. Wonder how it would do in a Malibu? Or a Colorado?

I wonder that all the time. The only thing I could imagine is that it's an expensive engine to build.

[james11]

I think that this is the firstt time in ten years that Nissan's 3.5 V6 was not on the list. Suprising.