You can't be this...
O.k. The only way you will raise the maximum effective compression ratio is if you make more power. This system is not about making more power, it's about minimizing pumping losses. If I have a NA engine that makes 100hp@6k rpm, and I turbo-charge the engine but make the same amount of peak power at the same rpm, there is no change in effective maximum compression ratio. It brings in X amount of air, to react with Y amount of fuel. The turbo just allows the system to use the energy of the exhaust, and the exhaust itself, to increase low load efficiency. Any car these days uses EGR in order to reduce NOx emissions and help out with
fuel economy.
I looked up your reference (Internal Combustion Engine Fundamentals, Heywood, page 837,838). Very interesting. Appears from his chart that BSFC minimizes at about 25% EGR.
The limit for EGR helping out BSFC is octane, and a homogeneous intake charge to a certain extent. An auto manf can't dump more EGR in the cylinder if the fuel auto ignites on the compression stroke because of too much heat. That's why E85 allows much higher low load efficiencies... More EGR can be run without causing the fuel to autoignite, which reduces pumping losses, giving diesel like efficiency. So, if, according to the EPA, something like a diesel Jetta gets 50% better mileage than a gasoline version, this technology would allow the gasoline version to approach that level of thermal efficiency at low load. What you are referring to is high load engine efficiency, which can be increased via higher CR. But that doesn't matter for most people because they usually don't have the pedal to the metal all the time.
For instance, a Camry built a decade and a half ago has ~33% peak BTE iirc, which isn't a big difference between the peak BTE of the Prius. But on the highway, the Prius gets well over twice the mileage. Why? Because the Prius has good low load efficiency, something like a minimum of 28% BTE, but the Camry drops down to maybe 12% BTE because the Camry suffers from lots of low load pumping losses. The Prius doesn't because of the Atkinson cycle, which is another way to minimize pumping losses. The downside of the Atkinson cycle is that torque is limited because a portion of the air drawn into the cylinder has to be pushed back out... So we have an engine that isn't "suitable" for the average driver. By supplementing it with an electric motor, peak power is increased, and other fuel saving features can be used. The use of EGR/VGTs with high octane fuel allows good mixing (something that's also need for lean burn systems) and high EGR at low load, which reduces pumping losses, and can result in a more efficient engine at the same power output w/o the need for a hybrid system. Most manufacturers aren't going to roll out these systems until E85 is established, so current engines aren't designed to run on them, and won't be unless E85 sticks around, not to mention the two to four years needed for development. VVT has been around for almost half a century, but it only penetrated the market within the last decade...
Fiat was the first auto manufacturer to patent a functional variable valve timing system which included variable lift. Developed by Giovanni Torazza in the late 1960s, the system used hydraulic pressure to vary the fulcrum of the cam followers (US Patent 3,641,988). The hydraulic pressure changed according to engine speed and intake pressure. The typical opening variation was 37%.
So there are delays when bringing any new device to the market. Now, if we have consistent, sizable E85 output in a decade, then I'm guessing we'll see these engines. But going back to what I said, I don't think we will because electric tech has been pushed back for too long. The Tesla Roadster is indicative of this.
*sigh*
