ORIGINAL: Blackflag
Those reports are all based on dyno testing. That's how you compare engines - back to back on a dyno, measuring fuel consumption, in a lab. Not according to what two mpg "window stickers" say for two different vehicles, different weights, different engines, different years. Seriously, give me a break.
And the Ford engine is a smaller engine. Or are you saying 5.4L vs. 7.0L is apples to apples now? Why do you want to ignore vehicle weight and engine displacement? Again - give me a break. I mean, in your previous post, you wanted to compare an Impala (though we dont' know what year) with a 5.7l engine to a new S Class with a 4.6l, and is 1000 lbs. heavier, different transmissions, different gearing... Give me a break. If you want to compare vehicles, then compare vehicles. But if you want to compare engines, it's done with dyno data.
If you want to be scientific, then be scientific. If you want to be a clown, then be a clown. But you know the difference. What you're trying to do is like saying the tires on a Cadillac must be less efficient than those on a Neon, because the Cadillac gets worse fuel economy. It's just a little more complicated than that.
Give me a break. First of all, I provide you with the information that those LT1 powered cars weight was less than one thousand pounds difference. The Cadillac version weighed only 18 pounds less and it still got the same mileage as the Impala SS did (weight difference of 429 pounds), and the newer Impala's (which was not what I was originally comparing) weight difference is less than one thousand pounds (754 pounds to be exact). If you read what I wrote you would know that. I provided gearing info on the Impala SS and Mercedes S-Class you ignored it. Also you need to get your facts straight, the new S-Class that I compared had a 5.5L not a 4.6L (infact I don't think they even have a 4.6L engine). The fact is the Mercedes has the advantage of more updated technology such as a better transmission, larger rims (15, 17 vs. 18s & 19s), a higher compression ratio, VVT system, from all appearances better arrowdynamics, etc. and it can't beat ten year old technology. It's especially sad that an old design routing back to the 50-60s gets better fuel economy than a current design with all the modern high tech advantages helping it.
You have been wrong over and over again on these engines. I provided tons of examples of both 2 valve pushrod conversions to OHC 4 valve engines and 2 valve OHC to 4 valve OHC engines on the same line and you ignore it and dismiss it. When you tried to dismiss it, I provide examples of other cases using the same engines in other models with evidence that disproved your attempts to dismiss it and you ignored that as well. You don't even know enough about the current engine market to know that there are still a few examples of 2 valve, 3 valve, and 4 valve headed engines on the same block line in production today. You even thought that Ford's VCT system was a multidisplacement system when it is nothing other than a VVT system.
One reason why many of these cars weight goes up sometimes after they switch from 2 valve to 4 valve is partly due to the increase in the engine's weight due to the changes. If the 4 valve system did have an advantage, it's lost by the weight and then some. If it is truely the path to pursue, this would not be an issue. The simple fact is that if 4 valves was the way to go, the most fuel efficient V8 cars on the market would be 4 valve engines, the problem is they are not 4 valve engines despite the displacement advantage that most of them have over most of these 2 valve pushrod models. Also the 2 valve pushrod models would be at the bottom of the fuel economy ratings. According to all the "official" sources, these 4-5.5 liter V8 engines should be the best in fuel efficiency and they are not. If it is a fact the evidence would be somewhe