Well, I had a chance to test on road the K&N air filters, last trip to chicago I was getting 21.3 MPG on the car at around 80 mph with ocasional spasms to 100+ (very few). Monday I went to Mound City, Ill to court for a speeding ticket (on my way back from chicago last trip, 126 mph on a 65), well the ticket did not go as I expected i had to pay a huge amount of money, much more than I've ever had to pay , but I can't complain, at least I didn't see jail over it!

Needless to say I watched my speed a little bit closer this time , I tried to keep the car at around 78 mph for the mst and a few time I passed 100 (very few times, one it was just for the picture at 58,000 miles odometer) at this rate I got the following:

Most of the trip the average was 23 mpg, there was a gas tank that was good for 23.47 MPG ! ! !, no a/c since it was "F"ing freezing up there!! I think I have a winner here! , 440 miles on a single tank of gas, I don't know of any other E55 that can do that, do you?

notice on the picture the engine is still running

 

This is just before the low fuel light came on and when the car turned 58,000 miles

 

This is when the low fuel light came on

 

Poch, man Im guessing you were in 4th gear or 5th while doing 100, I've seen a video, which i still have of an e55 doing 115 mph in third!

 

I think it was in 5th gear at that moment.

I just checked my video and at 6100 or 6150 rpm the car is about 108 mph and it shifts (it is supposed to hit the rev limiter at 6200 rpm which by then the car is going to be doing about 110 mph

 

yep your right
say do you have that SL55 vid of the review on motortrend?