LS1vazquez

The really sad thing is that the Cruze is really a spectacular car that delivers real world gas mileage and for Consumer Reports to go on a disinformation campaign means that somebody may actually miss out on it. This is no different then the New York Time reporter who did figures 8s in an underground parking garage in front of an charging station to intentionally run down the battery on a Tesla S, then reported that the car lacked a real world useful range.

The only sliver of light on this whole debacle is the people who read Consumer Reports also read Readers Digest and are probably all about to die off anyway. Good riddance with that BS.

Marc 85Z28

iTrader: (8)

I dislike CR as much as you do. However, it's either your disdain for them or your love for the little engine that couldn't that is clouding your judgement here.

Comparing these engines to larger more traditional engines is what was done. Of course they get great fuel milage in a compact car, but that wasn't the point of the article. They used the same platform!!!! How else would you do it?

LS1vazquez

The problem I have with the consumer reports article is that they only used 1 vehicle that is traditionally used as the litmus test for the capabilities of a turbo 4 application, and that vehicle horribly under performed in comparison to other similar models tested in other magazines. They also state that the 1.4 Turbo returned the same MPG as the 1.8 N/A model which is way out of line with real world results and nearly a mechanical impossibility as well.

Honestly, as a discriminating consumer who this magazine is specifically marketed towards, I would be forced to throw out the results of their "tests" based on this drastic anomaly and cannot draw any useful conclusions from this. This is a spectacular failure on CRs parts, but honestly what would you expect when your publishing an agenda driven hit job then what would you expect?

Marc 85Z28

iTrader: (8)

Mechanical impossibility?

In the "real world", you're looking at a difference of 1-2 MPG. Close enough.

http://www.fueleconomy.gov/feg/Power...ze&srchtyp=ymm

LS1vazquez

Did you even look at what you posted? The spread between the 1.8 and the 1.4T Cruze was
Nearly 6 MPG combined for user results. That's not "close enough". That's significant, especially when spaced over a 60 month ownership period.

A naturally aspirated 4 cylinder is not going to get the same gas mileage as a 4 cylinder with a turbo applied specifically for mileage purposes. If it was then they wouldn't bother with turbos to begin with.

FWIW, the Cruze has an Eco model that is specifically built with aero and body modificiations for MPG purposes. Its rated at 42 MPG highway. They do not offer an Eco model with the 1.8 and there is a reason for that.

TriShield

The biggest disinformation campaigns in the country are nearly every piece of advertising and marketing we see everywhere.

It most certainly isn't from a private consumer advocacy group who does not accept paid trips, advertising in it's pages or sites and buys all of their own products that they test and compare.

Marc 85Z28

iTrader: (8)

That's with 2 different transmissions. Give them the same gearing and you'll see near identical results.

jimmy169

How do most people here calculate their mpg here? I'm seeing some eye catching numbers that's making me wonder how my little 4 cylinder gets less. I write down the mileage on 2 consecutive receipts, subtract the difference and divide that total by the gallons written in the most recent receipt (I also fill up as soon as I see the light warning and fill it to max to try to keep things consistent when I do this). I get 21-23 mpg in my little mazda 4 cylinder, yet I'm seeing close to 30 here and am blown away because I don't even drive the car hard (why would I, it's a boring car). Our new vw turbo diesel gets around 30-32 mpg using the same method.

deft

iTrader: (7)

That's pretty much what I do. I use the "for dummies" method though and use www.fuelly.com saves me math and keeping receipts. Also it lets you look up other people's real world mpg numbers.

I actually drove a '99 TDI jetta (manual) for about 2 weeks. I observed somewhere around 44+ mpg.

94 White T/A

Fill up, reset trip meter, drive, fill up again, divide miles by the gallons it took to fill up

Z Fury

iTrader: (1)

Same. I also have a spreadsheet dating back to 2008 of all my fill-ups in all of my vehicles (including notes if a tank is 100% city, 100% highway, etc.). At this point I have a solid average of about 21 mpg in my 6-speed Z28 with a mix of 50/50 city/highway miles.

gocartone

iTrader: (4)

I don't understand how the hell you are doing it, but this-

If you want a good average check every time you fill up and keep track of your MPG for each tank, add them together, then divide. So 30mpg+35mpg+28mpg= 93, then divide by 3 = 31mpg average.

2002_Z28_Six_Speed

iTrader: (19)

My VW Passat with a 1.8T gas engine gets 29 MPG easily tank to tank. I can see 34 MPG with highway only numbers, average, if I keep the speed down. More if I slow down and follow trucks but not enough to be worth it.

SparkyJJO

iTrader: (11)

That's about the most convoluted way I've heard of to try to calculate mpg

Starting from a full tank, take miles driven and divide by the gallons needed to refill. Example, drive 280 miles, take 11.4 gallons to refill = 24.6 mpg.

LS1vazquez

They may be fair and impartial when it comes to expresso machines and hair dryers but their car analyses sucks.

It Still doesn't explain how they can pull mid-20s MPG from a Cruze when no other publication has managed numbers that low.

If your seeing something I'm not, please let me know.

LS1vazquez

That's with both cars being equipped with Automatics. Granted the 1.8 manual comes close the the 1.4T auto but with both trannies being the same your not going to make up the difference in gearing alone.

LS1vazquez

For my 2200 mile road trip I divided the total distance over total gallons purchased, which came out to 38 MPG. My sub 200 dollar fuel bill agrees with this.

94 White T/A

I would, but i dont care that much, lol. My car is for fun so i'm not worried about mpg too much

Hardrvin

iTrader: (1)

Why is it a mechanical impossibility? Same number of cylinders between the engines, so your friction losses should be pretty darn similar. If anything, your non turbo motor is probably lighter. And your non turbo probably has a higher compression ratio which boosts volumetric efficiency.

LS1vazquez

The primary driver of your efficiency of the motor isn't going to be the compression ratio. It's going to be a function of the density, temperature, and pressure of the atmosphere that the engine is functioning in.

A turbo allows more precise control over the atmospheric variables, and allows for more consistency in the burn over an overall performance spectrum that you are not going to get with a N/A motor. A turbo is an efficiency driver.

For example according to this paper right here; http://www.raeng.org.uk/education/di...lmax_Power.pdf

The power of a basic 4-stroke, 4-Cylinder motor can be calculated by applying this formula;



Wherein;



The last variable, n, is your efficiency of the motor itself.

The application of the turbo directly modifies the density variables, pA, which directly influences the output of the horsepower figure. Without the turbo, the density pA will be lower, which will output a lesser figure.

So yes, it is a mechanical impossibility because that's what the math works out to.