2 big problems with 2002 GT

[Technick]

Fuel vaporizing in the fuel rails is almost a non issue. If this were a carberated car then you would have a point Pizda. But with fuel pressure at close to 40 psi in the rails the fuel would have to get to over 350 degrees F. to come close to vaporizing. At that temp you have other major problems besides a fuel vapor concern. Also as soon as you turn the key on, fuel pressure jumps to that 40 psi range and would eliminate any vapor concern in a matter of 1 to 2 seconds. And 92 octane fuel as opposed to 87 is also a non issue. There is not that big of a gap in the fuels resistance to burning in only 5 octane, especially in a fuel injected engine at cranking speeds. Certianally at higher rpm's it is a bigger issue as the time available for the fuel to "light off" is significatly reduced. You do have a very valid point about the "winter blend" issue. The actual time of year really has no real bearing on it other than it is the winter time that such fuel is sold. The "winter blend" has a much higher level of alcohol or methonol to cut down on emissions since in the winter time there is usually a much bigger chance of weather inversions that keep the smog in place. The other down side to the methonol or alcohol additive is that these additives tend to evaporate off at a rather high rate which leads to a drastic reduction in the octane of the fuel which can cause pre-ignition issues. That is why Ford has gone to "returnless" fuel systems as the previous systems which pressurized and then de-pressurized the fuel as it was returned to the tank tended to "boil off" the additives.