[hightower99]

Originally Posted by jrobson

Yes they are best at 100%, everyone knows or should know that, your post shocks me, especially where you have the throttle at both 40% and 10% and still have 75% load!!

Theoretically yes they should be, but in the real world most engines run richer air:fuel ratios to protect the engine and make sure that no knocking occurs, which leads to worse SFC figures. In the real world the best SFC figures are achieved at the highest load that maintains closed loop control at 14.7:1 (or if Orbital is doing the testing 14.5:1).

Originally Posted by jrobson

SFC has nothing to do with real world driving, it means the engine create X amount of power for Y amount of fuel used,

Not quite. SFC means it takes X amount of fuel to produce Y amount of power per unit time. It is a direct measurement of the efficiency of the engine and therefore has quite alot to do with real world driving.

Originally Posted by jrobson

Honda did slightly better with their latest Vtec I believe called A-Vtec where instead of just adjusting lift it also adjusts timing, forget about ever getting a license though.

Honda VTEC systems have been able to change timing since 2001 (2002 in the US) with i-VTEC. One of the best valvetrain systems out there now is the BMW Valvetronic and VANOS technologies. Used together they provide infinitely variable lift control (the engine is throttled by the lift of the intake valves it no longer has a throttle valve) as well as infinitly variable timing.

read about it here:BMW Valvetronic