Just a little introduction: Today the brazilian league is starting it's first championship, based on the TBO class (XRT/RB4/FXO), with the first track being WE intl. The A class race is going to be held day 6 of this month. And i'm in the A class.
So, everyone is training for the championship those days, and me and a buddy of mine decided to make a test. That test was going to have 30 laps (same as in the race), i was going to race the XRT and he was going FXO.
We are precisely the same level in this track, we both have best lap times in the 1.57.1x range using the XRT, which is the car we are going to use for the championship. Before the test i thought the FXO would have to stop to change it's tires, but seems as i was wrong. We both finished the race without going into the pits, and our tires could still manage some 5 or 6 laps beyond the estipulated 30. Who finished in front?
FXO of course, with a 21 second advantage over my XRT. After the race we commented on the driving style we used. I had all my laps into the 1.57/1.58 range, without going into the grass once, and i remember only one braking mistake, with no major consequences. But he told me he was going totally relax, he went into the grass sometimes, missed some braking points, did some laps in the 2.00 range too.......and managed to win with a 21 second advantage over my XRT.
After that we reported our findings to the person in charge of the league, and the FXO's advantage was so proven that he decided to issue a passenger to all FXO drivers in the championship. But even then it is still faster, just with a slimmer margin.
Now let's get a technical view of the reasons for this advantage: Lighter weight - this one is the most obvious, the FXO weights almost 100 kg less than the XRT, and pretty much that compared to the RB4.
The second one, the FXO has a wider contact patch than the other 2, with 240 tires on all wheels, comparing to 245/225 on the XRT, and 215 on the RB4.
The third one, the FXO's transmission is the most efficient, with an 82% rating against 78% of the XRT, and 75% on the RB4.
The fourth one, is the boxer engine which gives it a better center of gravity.
And finally the fifth, as it's the car which uses the least fuel of those 3.
All of these would make sense if the car was hard to drive, but it's the easiest together with the RB4, and wears it's tires more or less the same as the other 2.
No need to say it had an advantage since S1 times isn't it? Just posting this so you guys know how it is, and hoping it will change in the next patches.