I've never dyno'd it but the manual says I'm supposed to gain about 10HP and 12 ft/lbs with E85, and I'd believe it. It's also a known issue with 3.0's that they love to ping, and my friend has gotten to the point that he sometimes runs midgrade in his even though it's stock and it runs better. So I guess not only is my engine NOT pinging, but it's gaining a bit of power on top. The 99 3.0's have an alcohol sensor, 24 lbs. injectors, and different combustion chambers as well. The tech library shows some of the differences between ethanol heads and standard heads, so my motor is actually a little different. The fuel lines are bigger as well (found that out when I accidentally bought the wrong fuel filter once lol), so I'd imagine if you had a factory E85 engine, that'd be easier for tinkering with E85 than trying to convert something - they've done a fair bit of changes just for the ethanol.