Aftermarket hybrid engine that plugs into any car? I think you'd have more luck with gasoline pills...at least those are cheaper.

Power, fuel economy, affordability. You can choose two.

Actually, the final drive ratio is the same between the two if my memory is correct (3.27) so I too am a bit surprised the ATS does not have a small MPG advantage. Only the 2LS Camaro has highway MPG rating of 30 because it has a 2.92 final drive ratio. Other V6 Camaros are rated at 28 MPG.

I wonder if there is something else affecting mileage for the ATS, or if the weight loss really doesn't help mileage much?

Keep in mind that just because a car loses mileage compared to another on the EPA test doesn't mean there is actually a difference in the real world. The EPA tests are inaccurate, and since car makers are more often trusted to run the test themselves (see Hyundai/Kia), they are almost not even useful for comparative purposes.

I agree that the mileage numbers used to satisfy the CAFE or EPA or whatever is getting more and more disconnected from what customers really see.

Especially for the V-8s, more and more gimmicky features...AFM, 1st to 4th, etc., are used to get high mileage numbers to satisfy the gov....and can be easily by-passed or unused by the driver...

The next gen LT-1 engines will have AFM in both manual transmission and automatic transmission cars. The Vette's will have a default driving mode that doesn't include AFM being active, you'll have to choose it.

If the government actually matches what drivers get for mpg, and eliminates the gimmicks that the factory can use to get a high rating, I think the party will really be over...lol...

3

haha yea. The site was somewhat sketchy. It would be nice if it were true though!

Already does, 1-6 and reverse :D

We're stuck with 14.7:1 fuel/air mixture. Big engines suck in more air which in turn needs more fuel. So displacement works against you. Therefore to get the best fuel economy you need smaller displacement. Turbo/blower engine would be one method, AFM the other. Either would need to be supplemented with reduced weight and better aerodynamics.

In either case, in part throttle it would run on reduced displacement, getting your 30 mpg. The turbo/blower effectively increases displacement by forcing in more air, so your 3.5 liter can be a 6 liter with boost. AFM of course just reduces/add cylinders.

I think GM should raise the price of Camaros (or at least the V8 models) to limit their numbers and play the CAFE averaging game that way. This would keep the cars at higher margins/quality/performance. Create a different fuel economy oriented car for the buyers that are about fuel economy eg Cruze SS, 130R etc.

BMW eventually went the turbo route. I hate AFM myself, so I would rather have a turbo v-6 or pay a gas guzzler tax when buying the v-8.

Lol smartass. You know what I meant. :D

Adding a turbo doesn't always increase fuel economy. The new GM Turbo V6 has near identical power and torque as the LS3 and gets the same gas mileage. The friction in an engine is a big determinant on fuel economy. A smaller engine might have to work harder, aka higher RPMs or throttle, than a larger engine to maintain a certain speed. In that case the increase in fuel economy might not be as noticeable because both engines could very well be using the same mass of air. The larger engine would require less throttle, and while it will "suck" in a larger volume of air for every stroke that volume of air will be at a lower pressure due to a greater pressure drop at the throttle and could be very similar in mass to that of a smaller motor using more throttle or spinning more RPMs. Also, when designing a car around turbos, the compression ratio must usually be lowered for reliability and longevity. This decreases the efficiency of the engine while it is not under load.

When the car goes into AFM mode, it may only be putting fuel into 4 cylinders, but it still has the friction of 8. Therefore, the other 4 have to work a bit harder, aka more throttle, which equals more air entering the 4 working cylinders. The only gain is you don't have as many combustion losses out of 4 cylinders vs 8 cylinders. That is why the gain in MPG seems minimal.

BMW went the turbo route mostly because it is a European based company. Most countries in Europe tax a car based on engine displacement. It's not a very fair system because nothing is an apples to apples comparison.

Very interesting, makes perfect sense - thanks for explaining.

Edit: I find it interesting that my 4-cyl 1993 Toyota pickup was rated 28MPG highway and the best mileage pickup said company makes in 2013 is rated 25MPG highway. 20 years of improvements in technology, and they have DEcreased 3MPG! Perhaps they measure it differently now. But still ... come on!

This is why I rebuilt the head at 316,000 miles rather than buy a new truck.

Also 20 more years of govt saftey regulations that require the trucks to be heavier and 20 years of consumers demanding more and more stuff in their trucks.

The new one is much bigger and heavier than the old one.