Riddle me this..MPG puzzle
 

Just so I don`t have to do ANOTHER 300 mile MPG test drive let me get anyones (Maybe a math guy) opinion on this.
So I wanted to check the MPG average of 2 different type fuel injectors (The types and part #'s being unimportant at this time.) So last weekend had set #1 in and drove 300 miles in a big circle (Visited the casino up in WV so not just a total waste of driving). Did the math and found I averaged 19.75MPG HIGHWAY. Refilled and drove back and forth to work all wekk and found that I averaged 14.47MPG CITY.
So..... This weekend installed set #2 in and drove the exact same 300 mile circle. Averaged 18.52MPG HIGHWAY, BUT I got stuck in 2 long traffic jams because of accidents which caused me to drive stop and go from between 0-20MPH for a total of 45 minutes!

SOOOO the question is even though set #1 averaged 1.25MPG more on the highway does the 45 minutes of city-like driving (Which would have dragged the MPG down to below 15) mean that set #2 was actually better?..Or maybe they were the same? Or there's no way of knowing?

only way to know for sure is to do the same uninterrupted trip you did with test #1. but for test # 2, even though you got stuck in 2 long traffic jams, your mileage only dropped by about 1, and i'd say thats pretty good! stop and go traffic will KILL mileage. i usually average about 13 MPG w/90% city and 10% highway driving. i got 10 MPG this past week because i ended up in a lot of stop and go traffic and no highway driving. plus i drive it daily to school which is only 1.5 miles away and get stuck in stop and go traffic waiting to get in the school parking lot!

Why would fuel injectors change fuel economy other than if they were totally shot and not atomizing very well? Your data sets seem to show about the same economy within the margin of error which is exactly what I'd expect from new injectors regardless of brand.

Different number of fuel port holes. 703's have 4 whereas stock xj have 1.