1 MPG Sells Chevys (apparently)

[DeckSetter]

Manufacturers are moving away from pushrod engines because they have more moving parts than OHC engines. No need to worry about pushrods bending or rocker arms jumping off when you don't have them in the engine to begin with. Reliability sells, ask Honda and Toyota.

That said, pushrod engines usually don't rev as high, so they're built for more low end torque. That puts your operating range closer to torque peak in normal driving and helps your economy. That's a good portion of why the '96 Park Avenue with a 3800 that my mom had would get 32-34mpg (with a high of 34.5) on the highway while my sister's Accord with a vtec 2.2 would never crack 30. (It also helps that the Buick would turn 2000rpm at 70mph, where the honda was closer to 3000).


All that said, I like my Cobalt XFE, but I wish it had a little more low end torque. I usually drive about 75% highway at 55mph, and going easy on it the last two tanks I've got over 39mpg average. This tank I got some road rage and drove 60 and I'm down to 36.2 (it's also just too much fun to bark 2nd gear...). The car is rated for 36 highway.


Also, I've had pretty good luck getting diesel fuel out of my clothes with lighter fluid... give it a try!

[MetroMPG]

Originally Posted by DeckSetter

This tank I got some road rage and drove 60 and I'm down to 36.2

You know you're an EcoModder when 60 qualifies as road rage

[RH77]

Posted at 1:19 AM CST, Sunday, 30-Aug-2009

Originally Posted by RH77

Looking back at the offerings from GM in the 4-Cylinder OHV department, we had the "Iron Duke" Tech-IV...

Jalopnik's "Engine of the Day", GM's Iron Duke...

Posted at 10:30 AM CST, Sunday 30-Aug-2009

Coincidence?

Probably

RH77
"Geez, I've resorted to quoting myself"

[Frank Lee]

Originally Posted by DeckSetter

Manufacturers are moving away from pushrod engines because they have more moving parts than OHC engines. No need to worry about pushrods bending or rocker arms jumping off when you don't have them in the engine to begin with. Reliability sells, ask Honda and Toyota.

All that said, I like my Cobalt XFE, but I wish it had a little more low end torque. I usually drive about 75% highway at 55mph, and going easy on it the last two tanks I've got over 39mpg average. This tank I got some road rage and drove 60 and I'm down to 36.2 (it's also just too much fun to bark 2nd gear...). The car is rated for 36 highway.

No need to worry about what?!? That pretty much never happens.

The main advantage of OHV is a more compact (energy dense) assembly.

The way we drive pretty much means there is no advantage to OHC.

[Old Tele man]

Originally Posted by Frank Lee

The way we drive pretty much means there is no advantage to OHC.

...which is all the more evidence that Detroit still doesn't "...see..." the American highway the way the American driver does.

...for instance, if they can make a 505hp high-performance car get 26-28mpg, then *why* don't they down/back-scale that technology into their smaller engines? I'm hoping this happens with the projected turbo-charged 1.4L for the new Chevy Cruze.

[pgfpro]

Originally Posted by Old Tele man

...which is all the more evidence that Detroit still doesn't "...see..." the American highway the way the American driver does.

...for instance, if they can make a 505hp high-performance car get 26-28mpg, then *why* don't they down/back-scale that technology into their smaller engines? I'm hoping this happens with the projected turbo-charged 1.4L for the new Chevy Cruze.

The Cruze looks promising.

Just as well, then, GM plans on launching the U.S.-market Cruze, scheduled to go into production at the company's Lordstown, Ohio, plant next year, with a new 1.4L direct-injection turbocharged four-cylinder engine under the hood. Details are sketchy, but it's believed this engine will deliver at least 130 hp and a healthy chunk of much needed mid-range torque, along with up to 44 mpg on the highway. Presumably, U.S.-spec Cruzes will also get much more crisply calibrated transmissions.

At least their moving toward DI technology.

[jkp1187]

Originally Posted by RH77

Posted at 1:19 AM CST, Sunday, 30-Aug-2009



Jalopnik's "Engine of the Day", GM's Iron Duke...

Posted at 10:30 AM CST, Sunday 30-Aug-2009

Coincidence?

Probably

RH77
"Geez, I've resorted to quoting myself"

I remember that thing. It was in that '88 Celebrity that got me through high school, college, and my job after college. It wasn't fast, but it was reliable.

[SentraSE-R]

Originally Posted by Old Tele man

...for instance, if they can make a 505hp high-performance car get 26-28mpg, then *why* don't they down/back-scale that technology into their smaller engines? I'm hoping this happens with the projected turbo-charged 1.4L for the new Chevy Cruze.

Well, when you're cruising at 1200 rpm with a 505 hp engine, and you need to accelerate, there's power to spare. If you're cruising with a 125 hp engine, there's virtually nothing left to tap, unless you've got a turbocharger to spin up, or electric boost, or some other auxiliary power to tap.

[Old Tele man]

...that's why they give you a "down-shift" option on automatics, or a next-lower gear on manuals...simply "do something about it!"

[SentraSE-R]

Downshifting kills your FE. The typical American driver will call the high geared econobox "gutless," bury his foot in 3rd gear up every hill, and whine about getting worse gas mileage than his neighbor in the Corvette. That's why automakers haven't downscaled the high gear fantasy to econoboxes.