As you probably know by now, BMW's Dries Vanthoor set the fastest single lap time in the Roar Before the 24 test for this weekend's Daytona 24 Hours.
BMW looked strong for the whole weekend, topping three sessions. Acura was fastest in the first session and Porsche took the fifth and sixth session. The sixth was particularly notable because it was topped by Neel Jani in the customer Proton Competition-run machine in very wet conditions.
However, as we know, one lap pace doesn't really tell the whole story in test or practice sessions. The real meat of the session is in the long run pace, which is obviously what the race will be made up of over the 24 hour period.
As we can see in the graph above, the two BMWs and the two Acuras were on top in the long run averages, as well as over one lap.
But, digging deeper, the #24 BMW, which had the fastest overall long run pace with a 1:37.110. This was only over four laps in the second session. Similarly, the #60 Acura's fastest average was set in the first session, over five laps this time.
If we remove these two, the fastest average was set by the #25 BMW, a 1:37.208, over 11 laps in the second session. This was over four tenths up, on average, compared to the #93 Acura, with a stint of 12 laps, also in the second session.
Either way, the two Porsches were quite a way off the BMWs and Acuras. The Porsche's fastest 'long runs' were also not that long; the #7 did its fastest time, a 1:37.939, in the fourth session over five laps. The slightly slower #6 set an average best of 1:38.019 in the first session, over seven laps.
The fastest Cadillac on average was only slightly behind the two Porsches. The #31 car, operated as ever by Action Express and sponsored by Whelen, set a 1:38.078 in the first session, over six laps.
And Lamborghini were quite a way off the other four manufacturers; eight tenths on average slower than the aforementioned #31 Cadillac, with the Italian manufacturer'sd fastest average long run coming in the second session, set over 13 laps. That's one bright spot for Lamborghini - that the fastest avertage stint was quite a bit longer than some of their rivals.
If we slim down the selected data to just the fastest car, on average over a long run, from each manufacturer (not counting the two customer Porsches), we can see the rather stark difference between them.
While Porsche and Cadillac are fairly close to each other, they are almost a second away from BMW and Acura, who are split by mere hundredths.
The Wayne Taylor Racing-run Cadillacs have some work to do, approaching half a second off the #31 car on average. But, given the car is brand new to them, plus the strength of the WTR squad and its drivers in general... they'll go away and do their homework to be right up there by race day.
Flipping it
Let's flip this around. We've looked at the fastest average long run data. Now let's look at the longest single run for each car and manufacturer, and the lap times opf those runs, across the six sessions the GTPs took part in (the seventh and final session was for bronze drivers only, from LMP2 and GTD).
The #7 Porsche, plus the #31 and #40 Cadillacs, had the longest uninterrupted (as in, they didn't pit) runs at the Roar, of 17 laps each.
Of these, the Porsche was the quickest — a 1:39.294. The #40 Cadillac wasn't far off, with a 1:39.416, both in the fifth session. The #31 Cadillac had its run in the third session, but was partially during a caution period so recorded an unrepresentative 1:56.178.
These caution periods could have skewed the data, as the cars obviously use less fuel when under full course yellow as they're going slower. The tyres, too, see less wear as less force is being put through them.
If we look at the times set on these longest runs, we can see the Acuras are quite a bit faster than the third fastest car, the #25 BMW. The Lamborghini is also up there in fourth, surprisingly.
Some cars — the two WTR-run Cadillacs, the #40 and the #10, #5 Proton Porsche, and the #6 Porsche, set their longest runs during the third session. This was interrupted by cautions, as already mentioned, and so these lap times, all in the 2:00s, are unrepresentative.
But, given the #31 Action Express-run Cadillac only achieved a 1:39.216 on its second longest run, of 12 laps, Cadillac may currently be lacking in long run pace. The WTR Cadillacs all had runs shorter than 10 laps other than the stints which were interrupted by cautions.
That said, the Porsches aren't looking too hot either. As mentioned, the #7 Porsche, with its 1:39.294, may also be struggling on the long runs.
BMW and Acura leading, but it's early days
So, in summary: however you look at the data, the Acuras and BMWs would appear to be on top right now. They have the quickest long run pace on average, plus the quickest long run pace looking at each car's longest run.
Neither achieved the 17 laps the Cadillacs or Porsche did, but it's only early days. The teams surely are not showing their full hands yet; we'll almost certainly only see truly what they've got to offer in the race, maybe even in the latter stages as things go down to the wire.
But nonetheless, it's interesting to examine this data to try and work out some trends. We'll be back with analysis from practice and qualifying for the Daytona 24 Hours later this week, plus other insights and interviews as the week goes on.
Feature image: © 2025 Brandon Badraoui / LAT Images / IMSA
Download The Racing Line, your personalised motorsport calendar, on iOS today to get up to date session times and customisable notifications for over 100 different series, including single seaters, sportscars, rally, bikes, and much more.