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Ghost
11-18-2008, 01:27 AM
A few points:
Yes, pushrod V8's are dinosaurs. Yes, we all run one in our boat. They may be dinosaurs, but they are a good solution to this particular problem. Boats require large doses of low rpm torque, and that is best achieved through large displacement or supercharging. Supercharging is much more expensive than displacement. Trucks fall into the same category, if to a lesser extent. Hence, when we shop trucks we still shop domestic. Cars and other lighter vehicles can get by quite well with less bottom end torque and can therefore afford to run smaller, more efficient motors.

Anybody know anything solid (good bad or otherwise) about the 4/8 cylinder switching engines? Long term reliability? It always seemed like a great idea to me, and the one ride I had in one seemed like it performed. I'm debating selling my beloved car for a truck.

gcarter
11-18-2008, 05:43 AM
When Cadillac did it back in the '80's, they tried to do a "4-6-8" scenario that was fundamentally flawed. Technology has come a long way since then. The Chrysler Hemi version of this scheme w/the "4-8" layout is flawless. I've driven some of the rental cars and they are as advertised. I've read articles about the engineering and it works.
In fact it works so well, others are now offering the same option.

CHACHI
11-18-2008, 06:35 AM
My father in law has the variable cylinder engine in his Suburban. If the info center on the dash never told you it was in 4 cylinder mode, you would never know.

Ken

smokediver
11-18-2008, 07:14 AM
my chevy truck works great !

chappy
11-18-2008, 07:49 AM
A buddy at work has a Dodge Hemi with it, he tows four sleds to Canada four times a year. His mileage claims are impressive when towing, but then again, he keeps telling me about a 12 pound largemouth he caught once.............:rolleyes:

Just Say N20
11-18-2008, 09:45 AM
I have a Dodge Magnum with the 5.7 Hemi. I bought it new 2 years ago, and it now has 67,000 miles on it. It has the cylinder reduction technology. It is seamless in it's transition. On trips when not towing, I have averaged as low as 21.5 mpg, and as high as 24.3 mpg for trips in the ≥300 mile range.

I tow a small 14' Jet boat, and get between 15.0 - 17.5 mpg when towing.

Around town I average 18.5 mpg IF I keep my foot out of it :frown:.

I do run 89 octane as recommended. I have read lots online about people running 87 octane to save the 10ยข/gallon, but it seems to cost them about 12% in gas mileage.

http://i26.photobucket.com/albums/c111/streb2005/ReflexxShinyNoPlate.jpg

zelatore
11-18-2008, 11:55 AM
I tow a small 14' Jet boat, and get between 15.0 - 17.5 mpg when towing.
Around town I average 18.5 mpg IF I keep my foot out of it :frown

By way of comparison, my '05 Ram 1500 Hemi 2wd quad cab (w/o deactivation) manages 15-16 combined if I'm gentle. Put it on the highway for a road trip where I cruise at 80-85, and it goes down to more like 14-15 Put it in the city with stop and go and I'm looking at more like 12-13. Towing the 22 on flatland on the highway is about the same.

Economical, it ain't

BigGrizzly
11-18-2008, 12:37 PM
I can tell you about the Honda VTECH engine it works good if you keep your foot out of it. The Honda Marine 225 uses it on the outboards and seems to have one of the highest fuel efficiency ratings in its class. The other part it has been pretty much bullet proof.

Donzi Vol
11-18-2008, 01:01 PM
my chevy truck works great !

What kind of mileage do you get out of it? I have a '04 Colorado and get anywhere from 18-21, depending on how I drive it. It has a 5 cyl Saab motor. I know...strange...

mattyboy
11-18-2008, 01:23 PM
we used kenny's brand new avalanche that has it , we towed out to the 20 cig run in Cinnci around 700 miles each way pulling the 20 cig on a brand new performance steel trailer we avg'd around 17 mpg pulled like we had nothing behind us think that was more the trailer than the truck though ;)

MOP
11-18-2008, 02:59 PM
What year did GM go to 8-4 on the suburbans?